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Kennedy, Nicholas Edwards. "Seismic Design Manual for Interlocking Compressed Earth Blocks". DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1049.
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Seismic Design Manual for Interlocking Compressed Earth Blocks
Nicholas Edwards Kennedy
This thesis presents a comprehensive seismic design manual to be used to design and construct simple Interlocking Compressed Earth Block (ICEB) structures in seismically active regions. ICEBs are earth blocks made primarily of soil and stabilized with cement. They have female and male stud mechanisms designed to interlock when stacked, eliminating the need for mortar. The blocks can accept reinforcement and grout after they are placed. While ICEB construction is similar to conventional masonry construction, current design code standards for masonry only partially capture the actual behavior of ICEB structures. This thesis seeks to supplement the existing masonry design procedures and tailor them for use with ICEBs.
Additionally, this paper presents a preliminary design of ICEB shear walls for a disaster reconstruction project in the Philippines. While many structures in Southeast Asia and the Malay Archipelago are constructed from earthen blocks, very few are engineered. Of those that are, a lack of formal design guidance specific to ICEB construction leaves most engineers and designers with conventional concrete masonry design practices, some of which are not applicable for use with ICEBs.
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Pringle, Sean Anthony. "Diagonal Tension Testing of Interlocking Compressed Earth Block Panels". DigitalCommons@CalPoly, 2016. https://digitalcommons.calpoly.edu/theses/1588.
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This thesis examines the use of diagonal tension (shear) testing to determine factors affecting shear strength of Interlocking Compressed Earth Block (ICEB) panels. This work expands on the current information available about strength properties of ICEB assemblies, which are dry-stacked, as opposed to having mortared beds. Variables such as block strength, grout strength and grouting pattern can influence the results of these types of tests and are examined in this investigation.
To study variables affecting diagonal shear strength, 9 panels were tested, consisting of blocks produced by a manual block press. Strength testing was adopted from common ASTM standards to determine constituent material properties. A modified version of ASTM E519 test procedure is used to perform diagonal tension testing. Imaging analysis, using a high resolution camera, was run simultaneously during testing to capture displacement histories of select panels.
It was determined that both block and grout strength significantly affect the shear strength of ICEB panels. Additionally, vertical grouting and block type also have a strong influence. Imaging analysis results confirm that the dominant failure mode in ICEB panels is bed joint sliding both pre and post peak load, with noticeable displacements at head joint locations on a few panels. Lastly, diagonal cracking along the block face was noticeable on several panels following peak load. Further testing remains to determine other factors affecting shear strength, namely, the application of normal pre-compression loads to the panel.
3
Rabie, Omar. "Revealing the potential of Compressed Earth Blocks : a visual narration". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/43006.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2008.Includes bibliographical references (leaves 63-64).
Compressed Earth Blocks (CEB) is a developed earth technology, in which unbaked brick is produced by compressing raw soil using manual, hydraulic, or mechanical compressing machines. Revealing the potential of an affordable sustainable material like CEB may help tackle today's fundamental challenges, social equity and environmental sustainability. For one year in India, I learned and practiced the basics of this technology in Auroville Earth Institute, and then conducted a group of design and construction experimentations for a natural resort project. Through these experimentations, I tried to reveal CEBs' capabilities through design innovation. The thesis captures my new understandings of the design competence of the material in relation to the design process, through narrating the story of this experience using images and a dialogue between the designer, mason, sponsor and the blocks themselves.
by Omar Rabie.
S.M.
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Bland, David William. "In-Plane Cyclic Shear Performance of Interlocking Compressed Earth Block Walls". DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/495.
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This thesis presents results from testing of interlocking compressed earth block (CEB) masonry shear walls. CEBs are low strength earth masonry units sometimes stabilized with cement or lime. The interlocking compressed earth blocks (ICEBs) used in this experiment are dry stacked interlocking hollow units, which can be reinforced and grouted after they are laid. Although significant research has been undertaken to optimize the material properties of CEBs, little has been done to investigate the performance of structural systems currently being built using this technology.
Test results are reported for three 1800 mm x 1800 mm wall specimens constructed with cement stabilized ICEBs and subjected to cyclic in-plane lateral loading. Wall specifications were varied to identify the shear performance of partial and fully grouted walls, and to observe the performance of a flexure dominated wall panel. It was determined that the shear strength of fully grouted walls is significantly higher than that of partially grouted walls and calculation of capacity based on current ACI 530-08 masonry provisions significantly overestimates the shear strength of ICEB wall panels. Based on the observed performance, recommendations are made for limiting the calculated nominal shear strength in design. Results also indicate that calculations based on simple bending theory conservatively predict the flexural strength of a fully grouted ICEB wall. Discussion of ICEB material properties and recommendations for design and construction procedures are included.
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Zarzour, Noura. "Modélisation, identification structurelle et estimation du facteur de comportement pour les bâtiments en maçonnerie géo-sourcée dans les zones sismiques". Electronic Thesis or Diss., Université Côte d'Azur, 2024. http://www.theses.fr/2024COAZ5056.
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L'utilisation de nouveaux matériaux de construction à faible émission de carbone dans les zones sismiques nécessite l'évaluation de la ductilité de la structure afin de concevoir correctement le bâtiment. Le manque d'estimation précise de performance structurelle limite l'utilisation de matériaux de construction écologiques. Une méthodologie fiable est établie pour la conception sismique des bâtiments construits par matériaux géo-sourcés. En particulier, un projet pilote de bâtiment en blocs de terre comprimée (BTC) dans une zone sismique moyen-élevé dans le sud de la France est réalisé. Partant de la caractérisation expérimentale des paramètres mécaniques du matériau, l'approche de conception sismique se concentre sur les caractéristiques modales de la structure, la ductilité attendue du bâtiment et l'évaluation des performances sismiques en termes de déplacement et de force.Le modèle de portique équivalent adopté pour la conception structurelle de la maçonnerie porteuse est validé pour deux cas d'étude : un bâtiment en pierre naturelle et un bâtiment en BTC. Le processus de validation du modèle consiste en la comparaison des fréquences naturelles et des déformées modales obtenues par analyse modale numérique et opérationnelle. Dans ce contexte, une campagne de mesure fournit la réponse structurelle aux vibrations ambiantes. Les paramètres modaux et l'amortissement structurel sont ensuite obtenus par des outils d'identification structurelle. L'analyse modale met en évidence l'impact de la rigidité de la dalle en bois sur la réponse dynamique des bâtiments en maçonnerie. Il est montré qu'une dalle en bois plus rigide avec une couche de renforcement améliore le comportement structurel de la maçonnerie sous chargement sismique, conduisant à des déformées modales globales.La vérification de la stabilité de la structure du bâtiment à l'état limite de quasi-effondrement est réalisée en termes de rapport déplacement cible à capacité, mais il est suggéré de vérifier également en termes de force, car cela peut être plus restrictif dans certains cas et moins dépendant de la convergence des procédures numériques. Le coefficient de comportement dans les codes sismiques pour la conception des bâtiments est défini pour les matériaux de construction typiques sur la base de l'observation des dommages et des modèles numériques. Une évaluation spécifique est nécessaire lorsque de nouveaux matériaux de construction sont adoptés parce que les codes du bâtiment ne fournissent que des valeurs limites. Cette thèse propose une procédure d'estimation du coefficient de comportement appliquée aux bâtiments en maçonnerie géo-sourcés, mais elle pourrait être adoptée pour tout matériau de construction. La méthodologie proposée pour estimer le facteur de réduction de force, puis le coefficient de comportement, intègre à la fois la demande sismique et la capacité du bâtiment. Pour cette raison, cette méthodologie peut être considérée comme une approche basée sur la capacité et la demande. Une analyse quasi-statique non linéaire est couplée à des analyses dynamiques et le coefficient de comportement est obtenu sur une base statistique. Les résultats sont comparés avec les estimations obtenues en utilisant des approches basées sur la demande, la capacité et l'approche N2. L'impact de l'adoption d'un modèle de bâtiment tridimensionnel ou d'un système équivalent à un seul degré de liberté avec ces méthodologies est analysé.La méthode proposée basée sur la capacité et la demande fournit, avec un temps de calcul réduit, une estimation fiable du facteur de réduction de force, proche des valeurs obtenues en utilisant l'approche basée sur la capacité appliquée à un modèle de bâtiment tridimensionnel considéré comme référence. Par conséquent, compte tenu de leur fiabilité et de leur efficacité, la méthodologie proposée pour l'estimation du facteur de comportement est adaptée à la pratique professionnelleThe use of new low-carbon construction materials in seismic areas requires the assessment of the structure ductility in order to properly design the building. The lack of accurate structural performance estimation limits the use of green construction materials.A reliable methodology is established for the seismic design of buildings constructed using geo-sourced materials. In particular, a pilot project of compressed earth block (CEB) masonry building in a medium-high seismic hazard zone in Southern France is developed. Starting from the experimental characterization of material mechanical parameters, the seismic design approach focuses on the modal characteristics of the structure, the expected building ductility, and seismic performance assessment in terms of both displacement and force.The equivalent frame model adopted for structural design of load-bearing masonry is validated for two case studies: a rubble stone masonry building and a CEB masonry building. The model validation process consists of the comparison of natural frequencies and mode shapes obtained by both numerical and operational modal analysis. In this context, a measurement campaign provides the structural response to ambient vibrations and then, the modal parameters and structural damping are obtained by structural identification tools. The modal analysis highlights the impact of timber slab stiffness on the dynamic response of masonry buildings. It is shown that a stiffer timber slab with a reinforced topping improves the structural behavior of the masonry structure under seismic loading, yielding to global mode shapes.The stability verification of the building structure at the near collapse limit state is performed in terms of target to capacity displacement ratio, but it is suggested to verify also in terms of force, since it can be more restrictive in some instances and less dependent on the convergence of numerical procedures.The behavior factor in seismic codes for building design is defined for typical construction materials based on damage observation and numerical models. A specific assessment is needed when new construction materials are adopted because building codes provide only boundary values. This thesis proposes a procedure for estimating the behavior factor that is applied to geo-sourced masonry buildings, but it could be adopted for any construction material. The methodology proposed to estimate the force reduction factor, and then the behavior factor, integrates both the seismic demand and building capacity. For this reason, this methodology can be considered as a capacity-demand-based approach. A nonlinear quasi-static analysis is coupled with dynamic analyses and the behavior factor is obtained on a statistical basis. The results are compared with the estimations obtained using demand-based, capacity-based and N2-based approaches. The impact of adopting a three-dimensional building model or an equivalent single-degree-of-freedom system with these methodologies is analyzed.The proposed capacity-demand-based-method provides, with a reduced computation time, a reliable estimation of the force reduction factor, close to the values obtained using the capacity-based-approach applied to a three-dimensional building model that is considered as a reference. Consequently, considering their reliability and efficiency, the proposed methodology for the behavior factor estimation is suitable for professional practice
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Ambers, Steven Ellis. "In-Plane Shear Wall Performance as Affected by Compressed Earth Block Shape". DigitalCommons@CalPoly, 2017. https://digitalcommons.calpoly.edu/theses/1705.
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This thesis investigates the in-plane shear performance of full-scale walls made from compressed earth blocks. Compressed earth blocks are a type of masonry where the blocks are composed of compressed soil and typically dry-stacked without mortar. Prior research has demonstrated that the in-plane shear strength of these blocks falls far short of capacities predicted by conventional masonry building codes, requiring new testing to develop effective and safe designs for seismic conditions. This thesis specifically studies the effects of block type and the use of grouted shear keys at the block head joints.
Three full-scale walls were constructed and tested under in-plane, cyclic loading. To compare the effect of block type on shear strength, one wall was constructed from Rhino blocks as used by the Center for Vocational Building Technology, while another used V-Lock blocks designed by the Vermeer Corporation. Apart from differences in size and interlock mechanism, the standard Rhino blocks have shear keys at the head joints which are not present on the V-Lock blocks. To examine the effect of these shear keys, a third wall was built from Rhino blocks with the shear keys removed.
The two standard block types displayed no major difference in strength that could not be attributed to grouted area or the presence/absence of the head joint shear keys. The Rhino block wall with shear keys reached a higher peak load relative to the grouted area but experienced a brittle drop in capacity after peaking, while the other two walls exhibited an extended loading plateau after the initial peak. All walls failed with cracking and block sliding along the main diagonals, a failure mode similar to conventional masonry. Proposals are made for modifying the equations for shear capacity from the Masonry Standards Joint Committee (MSJC) 2013 code for use in designing compressed earth block shear walls.
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Herskedal, Nicholas Anthony. "Investigation of Out-of-Plane Properties of Interlocking Compressed Earth Block Walls". DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/916.
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Interlocking compressed earth blocks (ICEBs) are cement stabilized soil blocks that allow for dry stacked construction. The incomplete understanding of the inelastic performance of ICEB building systems limits widespread acceptance of this structural system in earthquake prone areas. This thesis presents results from an experimental program designed to explore the behavior of ICEB walls, built according to current design practice in Indonesia and Thailand, and subjected to out-of-plane loading. A total of five reinforced and grouted ICEB walls were constructed and tested.
Results from experimentation show the current masonry design code, ACI 530, adequately predicts the yield strength of these walls. However, ACI 530 grossly over-predicts the ICEB wall stiffness. All tests showed flexural behavior and failure, except for one wall. A brittle failure was observed in one wall before reaching the predicted flexural strength, prompting a suggested maximum shear tie spacing. The testing results provide useful data for developing analytical models that predicts the seismic behavior of ICEB walls under out-of-plane loading.
A moment-curvature relationship was developed that accurately predicts the behavior of these walls in the elastic range as well as the inelastic range. By comparing the data provided by two walls of similar sizes, one including a pilaster and one without a pilaster, insight into stiffener elements was gained. Analysis of these two walls provides a limit on the length and height of ICEB walls without stiffener elements to prevent significant structural damage during a seismic event. In all, conclusions based on experimental data from ICEB out-of-plane loading tests are aimed to provide suggestions for ICEB construction in areas of high-seismicity.
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Bowdey, Thomas S. "Lap Splice Development Length of Rebar in Stabilized Hollow Interlocking Compressed Earth Blocks". DigitalCommons@CalPoly, 2016. https://digitalcommons.calpoly.edu/theses/1720.
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This thesis investigates the tensile performance of unconfined lap splices in specimens constructed from interlocking compressed earth block (ICEB) units. All lap splice specimens were constructed from hollow ICEB half units with one side grouting channel. ICEB units used in this research were exclusively produced from the Soeng Thai Model BP6 block press. The BP6 block press is currently manufactured in Thailand under the guidance and direction of the Center of Vocational Building Technologies (CVBT). All ICEB units and grout constructed for this research were created from mix proportions of soil, sand, cement, and water. Rebar bar sizes were restricted to M10 (#3) and M13 (#4) for all lap splice specimens due to the limited area of the hollow 2-inch diameter rebar cavity of the ICEB unit. The limited size and strength of the ICEB units also made the use of larger bar diameters impractical. Three ICEB unit types of varying strengths (3.78 MPa, 7.81 MPa, and 11.38 MPa) and three grout types of varying strengths (1.35 MPa, 7.47 MPa, and 15.50 MPa) were developed and used to construct all specimens. The measured ICEB lap splice specimen strengths were compared against the predicted strength calculated from the Masonry Standards Joint Committee (MSJC). Findings suggested that the MSJC design equation did not adequately predict the lap splice strength of specimens, particularly for specimens constructed from weaker materials. The measured ICEB lap splice results were used to create a new ICEB lap splice design equation. This paper also investigates the compressive performance of fully grouted ICEB prisms constructed from the range of ICEB unit and grout strengths stated above. Findings suggested that the compressive strength of fully grouted ICEB prisms were exclusively controlled by the compressive strength of the ICEB units used to construct the prism. The strength of the grout had no discernable effect on the strength of the fully grouted prism. A design equation was proposed to calculate prism strengths based on measured strength results of ICEB units.
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ZHEMCHUZHNIKOV, ALEXANDER. "INFLUENCE OF CLAY CONTENT AND SUCTION ON THE STRENGTH OF COMPRESSED EARTH BLOCKS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=27018@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
PROGRAMA DE EXCELENCIA ACADEMICA
Solo é um material de construção sustentável que tem sido utilizado por milhares de anos. As normas técnicas e recomendações existentes referente à construção de terra são baseadas em número limitado de estudos e dependem de materiais, condições climáticas e tradições locais. A compreensão dos parâmetros que influenciam o comportamento do solo compactado quando o mesmo utilizado em paredes e colunaas é essencial para a interpretação dos dados experimentais. Diversos estudos recentes analizaram taipa de pilão do ponto de vista da mecanica de solos nçao saturados, observando o decrescimo da resistência com a diminuição da sucção, causada por exemplo pelo aumento da humidade do ar. Porém, não hã uma pesquisa semelhante pertinente aos blocos de solo compactado. O objetivo do presente trabalho foi verificar a influência do teor de argila, dencidade e sucção na resistência dos blocos de solo compactado. Foram utiliazdas quatro dosagens de solo artificial que consistiu de areia, pó de quartzo e argila caulitinitca. Para cada dosagem, amostras estaticamente compactadas na umidade ótima e no ramo seco foram ensaiadas variando-se a sucção. Ao contrário dos resultados encontrados comunmente na literatura, a resistência das amostras diminuiu com o aumento da sucção, enquanto a influência das condições climáticas como umidade e temperatura foram mínimas. As conclusões feitas no presente trabalho podem ser utilizadas nos projetos de construção sustentável com emprego de blocos de solo compactado.
Soil is a sustainable construction material that has been used traditionally for thousands of years. In general, earth construction specifications are based on common knowledge. Existing recommendations tend to be supported by a limited number of studies and depend on local materials, climatic conditions and historical background. The lack of understanding of compacted soil behavior, in particularly its strength, may have prevented a wider application of earthen construction materials in housing. Understanding of the soil properties and parameters that influence its performance when used in walls and columns is essential for interpretation of experimental data. Recently a number of studies have analyzed rammed earth considering unsaturated soil mechanics, which suggest loss of strength following decrease in suction values, for example provoked by the increase in relative humidity. However, there is a lack of such research pertaining to compressed earth blocks (CEBs). The objective of this study was to verify the influence of clay content, density and suction on the strength of CEBs. Four soil mixes consisting of sand, quartz powder and kaolinitic clay were used. For each soil mix statically compacted samples with densities corresponding to optimum and dry of optimum moisture contents were tested for a range of suctions. Unlike reported in the literature, the results showed loss of strength following increase in suction values, while only small variations were registered for suctions corresponding to a wide range of RH and temperature conditions. The findings can be of use for specifications relating to construction of sustainable housing using CEBs.
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Stirling, Bradley James. "Flexural Behavior of Interlocking Compressed Earth Block Shear Walls Subjected to In-Plane Loading". DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/593.
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This thesis investigates the flexural behavior of interlocking compressed earth block (ICEB) shear walls. In-plane cyclic tests were conducted to evaluate the performance of three flexure dominant large scale ICEB specimens: a slim wall with a 2:1 height to width aspect ratio, a flanged wall, and a wall with an opening at the center. Following the experimental investigation, two types of analyses were conducted for calculating the ultimate strength of flexure dominant ICEB walls: a nonlinear static analysis model assuming lumped plasticity and a plastic analysis model. In addition, incremental dynamic analysis was conducted to address the seismic performance of flexure dominant ICEB buildings. Based on the database from the incremental dynamic analysis, the collapse potential of demonstration ICEB buildings were compared for the countries of interest.
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Chumbinho, Joana Martins. "Otimização de solos para a produção de blocos de terra compactada". Master's thesis, Universidade de Évora, 2017. http://hdl.handle.net/10174/21331.
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Surgindo da necessidade de criar novos métodos construtivos mais sustentáveis, com a uti-lização de materiais ecológicos, é cada vez mais procurada a construção tradicional em terra. Este método é conhecido como uma das mais antigas técnicas de construção, genero-samente utilizada ao longo da história, até ao decaimento da sua utilização, aquando do aparecimento de técnicas atualmente conhecidas como convencionais.
Esta dissertação pretende dar a conhecer outras soluções de construção em terra, onde são elaborados blocos de terra compactada, com a incorporação de diferentes adições, com o objetivo de melhorar as propriedades mecânicas e físicas dos mesmos. Os blocos foram avaliados experimentalmente, permitindo verificar a evolução da resistência mecânica, e a sua capacidade de absorção de água, tornando-se possível compreender o comportamento e adequabilidade da alvenaria de blocos de terra compactada; Abstract:
The need to create more sustainable constructive methods with the utilization of ecological materials, made the compressed earth blocks construction more pursued again. This method is known for being one of the eldest and commonly used techniques in construction, however evolution of the construtive technologies caused a decay on the traditional techniques, as the compressed earth blocks.
This dissertation intends to show new compositions of compressed earth blocks construction, where are elaborated compressed earth blocks, with the incorporation of different additions with the objective of improving the mechanical and physical properties of the compressed earth blocks. The blocks were evaluated experimentally, allowing to verify the evolution of the mechanical resistance and the capacity of water absorption of the blocks, to understand the behaviour and the masonry suitability of the compressed earth blocks.
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Banker-Hix, Wyatt Adair. "The Effect of Clay, Cement and Fibers on the Strength and Durability of Compressed Earth Blocks". DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1233.
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This Thesis examines the effect of soil characteristics, cement content and fibers on the strength and durability of compressed earth blocks (CEBs). This work expands on the available information regarding the constituent properties which affect the compressive and tensile strengths and durability of CEBs. Additionally, little research on the subject of synthetic fibers and their effect on strength and durability of CEBs is available and this work provides an initial study in this area.
To study the effects of fibers, as well as confirm the trends of previous research regarding the effects of clay and cement, 27 unique batches of CEBs were pressed and tested using a Vermeer BP 714 block press. Three different soil types and two fiber types were utilized. The compressive strength, modulus of rupture (MOR), absorption, and durability were measured on over 185 specimens. The strength and absorption tests were adapted from common ASTM International test methods for similar materials, while the durability test was a uniquely developed method to quantify durability by measuring mass loss during drying and wetting cycles.
After the testing regimen was completed, a trend between clay content and strength could not be determined. Durability testing suggested that as clay content decreases, durability increases. A linear relationship was found between cement content and strength, which was confirmed during durability testing. The addition of different fibers did not have an effect on the peak strength of CEBs, although it appears they may decrease the durability. The gross versus net unit strengths of CEBs were examined due to the unique shape of the CEBs utilized. Additionally, a mathematical expression relating the MOR to the compressive strength was developed.
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Sousa, Soenia Marques Timoteo de. "Efeito da ativação alcalina dos aluminossilicatos nas propriedades mecânicas e microestruturais de compósitos argilosos prensados". Universidade Federal da Paraíba, 2011. http://tede.biblioteca.ufpb.br:8080/handle/tede/5328.
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Previous issue date: 2011-03-31Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
In the chain of energy and motor fuel, in agreement with the policy to adopt green technologies, Brazilian government has encouraged the installation of biodiesel plants to produce an alternative, less polluting and less cost fuel to replace diesel and gasoline. In Paraíba State, the Biodiesel Program was created by the Law 7761 of June 15, 2005. This program initially aims to accomplish two goals: generating clean energy and social inclusion of family farmers. A plant will be built in Campina Grande and will occupy a total area of 704 m2 with a production capacity of approximately 134,000 liters/day (40 million liters/year). These biodiesel plants generate by product in the production process. Some of then, as the water from purification of the biodiesel, have high pH. It is necessary to find a way to avoid that these waste causes high environmental impact. The alkaline activation of certain materials has been studied as an alternative to Portland cement binder. In this work clay-based alkaline activated composites were investigated, with the aim to produce construction blocks. Soil available locally and metakaolin were used. As alkaline activators the Na2SiO3 (sodium silicate) and the NaOH (sodium hydroxide) were obtained commercially, but the KOH (potassium hydroxide) was obtained from the wash water from biodiesel production process. The activators and some small percentage of metakaolin are mixed with the soil and water, and the mix was compressed by a static strength of about 2 MPa, which is commonly provided by hand presses for the fabricate compressed earth blocks. The results show the feasibility of such use of liquid waste from biodiesel. The mechanical strength depends on the concentration of metakaolin, which can reach up to 17 MPa for composites with 22% activated alkaline soil. The durability, physical properties and microstructures of samples with different compositions were also studied.
Na cadeia da energia e do combustível automotor, dentro da política mundial de adoção de tecnologias verdes, o governo brasileiro vem incentivado à instalação de usinas de biodiesel, material que está sendo empregado como uma alternativa, menos poluente e de menor custo em substituição ao diesel e à gasolina. Na Paraíba, o Programa de Biodiesel foi criado através da Lei Estadual 7.761 de 15 de junho de 2005. O projeto visa inicialmente cumprir duas metas: geração de energia limpa e inclusão social de agricultores familiares. Uma usina será construída em Campina Grande, com capacidade de produção de cerca de 134 mil litros/dia. Estas usinas geram, no processo produtivo, resíduos. Faz-se necessário encontrar uma alternativa para que os resíduos tenham o menor impacto possível no ambiente. Aqueles provenientes da purificação do biodiesel são alcalinos. A ativação alcalina de certos materiais tem sido estudada como um ligante alternativo ao cimento Portland. Neste trabalho estudou-se a formação de um compósito à base de argila alcalinamente ativada para confecção de blocos para construção, nos quais foi usado um solo local e metacaulinita. Como ativadores alcalinos empregaram-se o silicato de sódio, hidróxido de sódio e o hidróxido de potássio proveniente da água de lavagem de biodiesel. Os ativadores são misturados com o solo e a mistura recebe uma compactação estática da ordem de 2 MPa, que é a comumente fornecida por prensas manuais para a fabricação de blocos prensados de terra crua. Os resultados mostram a viabilidade desse tipo de emprego do resíduo líquido de biodiesel. A resistência mecânica depende do teor de ligantes, podendo atingir valores de até 17 MPa para compósitos com 22%de solo alcalinamente ativado. A durabilidade, as propriedades físicas e microestruturais de amostras com diferentes composições foram estudadas.
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Rocha, Mafalda de Azevedo e. Castro Amaral. "Sustentabilidade e arquitetura bioclimática nos trópicos : tipologias sustentáveis e (re)desenho urbano em São Tomé e Principe". Master's thesis, Universidade de Lisboa. Faculdade de Arquitetura, 2015. http://hdl.handle.net/10400.5/8955.
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Laibi, Babatounde. "Comportement hygro-thermo-mécanique de matériaux structuraux pour la construction associant des fibres de kénaf à des terres argileuses". Thesis, Normandie, 2017. http://www.theses.fr/2017NORMC265/document.
Texto completo da fonteResumo:
Les briques de terre compressée (BTC) à la façon traditionnelle au Bénin présentent de piètres propriétés mécaniques, ce qui explique que les populations recourent aux parpaings de ciment relativement trop couteux et dont l’emploi affecte fortement les ressources en eau et en énergie. Ce travail propose des pistes d’amélioration des BTC pour l’écoconstruction par l’ajout de fibres végétales à des sols usités localement pour la construction. Cette stratégie permet de valoriser les matières premières minérales et végétales dans un domaine d’activités qui concerne une grande partie de la population. Dans un premier temps, un sol a été choisi d’après sa composition chimique, ses propriétés physiques, mécaniques et technologiques. Le choix de la fibre de kénaf pour le renforcement de la matrice minérale se justifie par ses excellentes propriétés mécaniques spécifiques et sa disponibilité à très faible coût. Les effets des fibres sur le comportement du sol au jeune âge, puis sur les comportements mécanique et hygrothermique des matériaux consolidés sous 5 MPa (pression applicable avec les équipements facilement disponibles au Bénin), ont été étudiés pour trois taux massiques de fibres (0,5%; 1% et 1,5% relativement au sol) dans différentes longueurs (5, 10, 20 et 30 mm). Les résultats indiquent une nette amélioration du comportement mécanique des BTC renforcés par le kénaf en termes des résistances à la flexion et à la compression, et de la résistance à la rupture catastrophique (comportement pseudo ductile). Les résultats les plus élevés sont obtenus pour une teneur de 0,5% de fibres de longueur 30 mm. L’ajout de ciment seul au sol fibré (taux de 3, 5 et 7%) ou de ciment associé au laitier de haut fourneau (taux de 3-5% et 5-10%, respectivement) permet en sus d’améliorer de façon importante la résistance à la prise d’eau. Les meilleurs résultats sont obtenus avec 5% de ciment et 10% de laitier de haut fourneau. Les mesures réalisées en chambre biclimatique ont permis de caractériser les matériaux comme paroi séparatrice, en étudiant les transferts de chaleur et de vapeur d’eau. Les résultats mettent en évidence l’effet significatif de l’ajout d’un liant au BTC : L’ajout d’un liant diminue le déphasage et augmente l’atténuation du matériau. Les meilleurs résultats de comportement hygrothermique sont obtenus pour le sol fibré.Cette étude démontre qu’il est possible de produire au Bénin, à partir de matières premières locales et avec des équipements peu onéreux, des éco-matériaux aux propriétés mécaniques et hygrothermiques satisfaisantes pour la construction d’habitat de type R+1Traditional Compressed Earth Blocks (CEB) in the Republic of Benin have poor mechanical properties, this justifies why people rely on relatively expensive cement blocks; the use of which greatly affects resources such as water and energy. In this work we have proposed ways to enhance CEB properties for eco-construction by adding plant fibers to locally used construction's soils. This strategy makes it possible to value mineral and vegetable raw materials in a field of an activity that is common to a large part of the population. At first, a soil was chosen according to its chemical composition, its physical, mechanical and technological properties. The choice of kenaf fiber for the reinforcement of the mineral matrix isjustified by its excellent specific mechanical properties and its availability at very low cost. The effects of fibers on soil behavior at young age and on the mechanical and hygrothermal behavior of consolidated materials under 5 MPa (pressure applicable with equipment readily available in Benin) were studied for three mass content of fibers relatively to the soil (0.5% 1% and 1.5%) and different lengths (5, 10, 20 and 30 mm). The results indicated a remarkable improvement in the mechanical behavior of kenaf-reinforced CEBs in terms of flexural and compressive strengths and tolerance to damage. The highest results were obtained with 0.5% of fibers 30 mm long. The addition of a binder (3, 5 and 7% of cement) or (3-5% and 5-10% of cement and blast furnace slag mix) allowed an important reduction in water uptake. The best mechanical results were obtained for a biocomposite made up with BAK soil, 0.5% of flax fibers 30 mm long and a mix of 5% cement and 10% blast furnace slag. Measurements carried out in a biclimatic chamber made it possible to characterize the hydric and thermal behavior of the soil-based materials. The addition of a binder decreases the phase shift and increases the attenuation of the material. These different results show that it is possible to produce in Benin with the available equipment, CEB with mechanical and hygrothermal properties sufficient enought for the construction of type R + 1 habitat
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Namango, Saul Sitati. "Development of cost effective earthen building material for housing wall construction: investigations into the properties of compressed earth blocks stabilized with sisal vegetable fibres, cassava powder and cement compositions". [S.l.] : [s.n.], 2006. http://se6.kobv.de:8000/btu/volltexte/2006/6.
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Cabrera, Vargas Marlo Manuel, e Ormeño Jose Daniel Tello. "Mejora de las propiedades mecánicas de los bloques de tierra comprimida (BTC) reforzados con cemento y fibra natural". Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/654614.
Texto completo da fonteResumo:
Existe en la actualidad una intensa búsqueda constante de recursos y tecnologías menos contaminantes, que consumen menos energía en la construcción. El bloque de tierra comprimida (BTC) reforzado con fibra natural puede ser una alternativa efectiva. Este estudio presenta los resultados de una investigación para establecer las propiedades mecánicas del BTC estabilizado con cemento y reforzado con fibra de bagazo de caña. Se consideró evaluar las siguientes combinaciones BTC, BTCE (6% de cemento), BTCB-I (4% de cemento y 0.5% de fibra) y BTC-II (4% de cemento y 1% de fibra). Además, los resultados de las pruebas mecánicas se compararon con normas establecidas y con otras investigaciones relacionadas al tema.
Se observó que, con el aumento de cemento, la resistencia de los bloques de tierra comienza a incrementarse gradualmente. Sin embargo, se puede reducir la cantidad de cemento reemplazándola con un mínimo de 0.5% de fibra natural en estado seco, representando bajas pérdidas de resistencia. De la investigación se sugieren analizar coeficientes de diseño a diferentes condiciones, considerando que con un mínimo de 4% de cemento y un 0.5-1% de fibra fue suficiente para producir BTC que cumplan con los requisitos estipulados en la norma peruana.There is currently an intense constant search for less polluting resources and technologies, which consume less energy in construction. Natural fiber reinforced compressed earth block (BTC) can be an effective alternative. This study presents the results of an investigation to establish the mechanical properties of BTC stabilized with cement and reinforced with cane bagasse fiber. It was considered to evaluate the following combinations BTC, BTCE (6% cement), BTC-I (4% cement and 0.5% fiber) and BTC-II (4% cement and 1% fiber). In addition, the results of the mechanical tests were compared with established norms and with other research related to the subject. It was observed that, with the increase of cement, the strength of the earth blocks begins to increase gradually. But nevertheless, the amount of cement can be reduced by replacing it with a minimum of 0.5% natural fiber in the dry state, representing low resistance losses. From the reach it is suggested to analyze design coefficients at different conditions, considering that a minimum of 4% cement and 0.5-1% fiber was enough to produce BTC that comply with the provisions of the Peruvian standard.
Trabajo de investigación
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Lin, Wei. "Etude tectonique de l'avant-pays méridional de la chaîne Dabie-Qinling (Nord du bloc de Chine du Sud)". Phd thesis, Université d'Orléans, 2000. http://tel.archives-ouvertes.fr/tel-00767063.
Texto completo da fonteResumo:
L'AVANT PAYS MERIDIONAL DE LA CHAINE QINLING-DABIE CORRESPOND A LA PARTIE NORD DU BLOC DE CHINE DU SUD. (OU BLOC DU YANGTSE). CETTE REGION EST CONSTITUEE D'UNE SUCCESSION DE BASSINS ET DE RIDES OU DOMES METAMORPHIQUES D'AXE E-W. AU S. DU DABIESHAN, ON RENCONTRE SUCCESSIVEMENT L'AVANT PAYS PLISSE DU YANGTZE, LE DOME DE LUSHAN ET SON EQUIVALENT LATERAL PLUS SUPERFICIEL DU JIULINGSHAN, LE BASSIN DE PINGXIANG, LE DOME DU WUGONGSHAN ET LE BASSIN D'ANFU. OUTRE LA TECTONIQUE CENOZOIQUE QUI N'A PAS ETE CONSIDEREE ICI, LA STRUCTURE REGIONALE RESULTE DE DEUX EVENEMENTS TECTONO-METAMORPHIQUES RESPECTIVEMENT D'AGE CRETACE (CYCLE YANSHANIEN) ET TRIASIQUE (CYCLE INDOSINIEN). L'EVENEMENT CRETACE EST CARACTERISE PAR LA FORMATION D'HEMI-GRABENS REMPLIS DE SEDIMENTS TERRIGENES CONTINENTAUX (COUCHES ROUGES) DONT L'OUVERTURE EST CONTROLEE PAR DES FAILLES NORMALES FRAGILES. LA FAILLE DE TAN-LU EST L'ACCIDENT MAJEUR DE CE SYSTEME. L'EXTENSION FRAGILE SUPERFICIELLE PEUT S'ACCOMPAGNER D'UNE DEFORMATION DUCTILE PROFONDE QUI MYLONITISE DES GRANITOIDES. CEPENDANT DE NOMBREUX MASSIFS GRANITIQUES D'AGE CRETACE MOYEN A INFERIEUR SONT DES PLUTONS SYNTECTONIQUES DONT LES BORDURES SONT MYLONITIQUES ET LE CUR EST ORIENTE A L'ETAT SUBSOLIDUS. L'EVENEMENT TRIASIQUE EST DATE STRATIGRAPHIQUEMENT DANS LES BASSINS PAR LA DISCORDANCE DU TRIAS SUPERIEUR SUR LE PALEOZOIQUE-TRIAS INFERIEUR PLISSE ET RADIOMETRIQUEMENT DANS LES DOMES PAR DES AGES AUTOUR DE 220 MA. LES ROCHES SEDIMENTAIRES SONT AFFECTEES PAR DES STRUCTURES EXTENSIVES EN COLLAPSE : GLISSEMENTS BANCS SUR BANCS DANS LA PENTE, FAILLES NORMALES, PLIS PLONGEANTS. CES STRUCTURES SONT SYMETRIQUES ET DIVERGENTES PAR RAPPORT A L'AXE DES DOMES. UNE DEFORMATION DUCTILE EXTENSIVE APPARAIT AUSSI DANS LES ROCHES METAMORPHIQUES. DANS LE DABIESHAN, LA DEFORMATION DUCTILE MAJEURE EST UN CISAILLEMENT VERS LE NW QUI ACCOMMODE UNE PARTIE DE L'EXHUMATION DES ECLOGITES DE UHP PENDANT LEUR RETROMORPHOSE EN AMPHIBOLITE ET UNE MIGMATISATION. CETTE TECTONIQUE D'EXHUMATION EST INTERPRETEE COMME UN PHENOMENE D'EXTENSION SYNCONVERGENCE. DES DEFORMATIONS COMPRESSIVES EXISTENT DANS LES MASSIFS DE JIULINGSHAN, LUSHAN ET DABIESHAN. LA COLLISION CHINE DU NORD-CHINE DU SUD SE PROPAGE AINSI SUR UNE GRANDE DISTANCE DANS LE BLOC DE CHINE DU SUD. DES CISAILLEMENTS SYNMETAMORPHES CONDUISENT A UN ECAILLAGE DE LA CROUTE DU BLOC DE CHINE DU SUD. LE BLOCAGE DES CHEVAUCHEMENTS PROVOQUE LA FORMATION DE DOMES EN CONTEXTE GLOBALEMENT COMPRESSIF. SUR LES FLANCS REDRESSES DES DOMES, DES STRUCTURES EXTENSIVES SONT DONC INDUITES PAR UNE TECTONIQUE COMPRESSIVE. LA FORME ACTUELLE DES DOMES EST ACCENTUEE PAR LA MISE EN PLACE DES PLUTONS LORS DE L'EVENEMENT DU CRETACE.
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Ipinge, Iyambo. "Durability of compressed stabilised earth blocks". Thesis, 2013. http://hdl.handle.net/10539/12393.
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The world is facing the dilemma of housing its ever increasing population whilst preserving the
environment for the needs of future generations. The use of alternative technologies such as
the Hydraform compressed stabilised earth block (CSEB) in building construction is burgeoning.
The Hydraform block is irregular in shape and thus a specific test method for the assessment of
the blocks strength has been developed.
Owing to the Hydraform blocks irregular shape, a specific test method for the characteristic
unconfined compressive strength of the Hydraform block had to be developed. Hydraform
blocks produced with varying soil properties and stabilised with various cement contents are
evaluated by means of the developed test method. Saturated and unsaturated block strengths
are evaluated where it has been found that in certain cases as much as half of the dry strength
of blocks is lost when blocks become saturated.
Three chemicals, namely Masterseal 550, Masterseal 501 and Acronal S400 are used to
waterproof blocks and in turn increase the saturated strength and durability properties of
Hydraform blocks.
Compressive strength and other CSEB durability measures such as resistance to abrasion, resistance to water uptake and water sorptivity testing are used as measures of the durability of
CSEBs. These measures are used to compare blocks produced without chemicals to blocks
produced with chemicals additives.
Through the mentioned durability measures it is found that Masterseal 501 increases the dry
and saturated strength properties above that of any other chemical additives. To the contrary,
it is found that Masterseal 550 and Acronal S400 completely protect Hydraform blocks against
the ingress of water, whereas Masterseal 501 allows water absorption into the blocks. In
addition, it has been found that increase of cement concentrations in blocks in the most
effective measure to resist abrasion or wind and rain driven erosion.
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Tattersall, Graham. "Structural Testing of Compressed Earth Blocks and Straw Bale Panels". Thesis, 2013. http://hdl.handle.net/1974/8442.
Texto completo da fonteResumo:
Globally, there is a need for alternative building materials that require less energy to produce than conventional materials. These alternative materials have gained popularity in recent years, however there is a need to better understand their physical properties in order to increase confidence in their use. As such, a testing program was undertaken to investigate the structural properties of some of these materials.
A series of compressed earth blocks made from a mixture of earth and cement compressed to 8 - 12 MPa were tested for their compressive capacity in masonry prisms. The blocks had been weathered for one to two years. The blocks with no cement had a capacity of 2.22 MPa, while cement stabilized blocks had a capacity of 8.11 MPa. Weathering did not result in any significant reduction in the strength of the blocks.
Bales of high density straw were tested both with and without cement plaster skins. Unplastered bales exhibited a stiffness between 0.3 - 0.7 MPa when oriented Flat, and 1.2 MPa on edge. The bales had a dilation ratio between 0.1 - 0.3 in the Flat orientation and averaging 3.5 in the Edge orientation. The high density bales plastered with cement plaster exhibited ultimate strengths averaging 171.2 kN/m. Capacity was heavily dependent on plaster strengths, and when normalized for plaster strengths, high density bales had capacities lower than those of regular density bales tested previously (34.1 kN/m/MPa compared to 44.3 kN/m/MPa).
Three walls made of straw with cement plaster were constructed with pin-ended conditions to study the effects of buckling in straw bale walls. The average capacity was 12.8 kN/m/MPa when normalized for plaster strength. Pin ends resulted in plastic hinges forming more easily in the walls, and pin ended specimens had a 75% reduction in strength compared to previous tests of "standard" end conditions. Taller walls also resulted in reduced strengths.Thesis (Master, Civil Engineering) -- Queen's University, 2013-10-30 09:26:46.491
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Moreira, Thomas Wilfried Sturm. "Experimental characterization of dry-stack interlocking compressed earth block masonry". Doctoral thesis, 2015. http://hdl.handle.net/1822/36054.
Texto completo da fonteResumo:
Tese de Doutoramento em Engenharia Civil (área de especialização em EstruturasEarth is still used as a building material to construct houses in Africa. One of the most common techniques is the masonry of sun dried or kiln fired mud bricks with earth mortar. Although this technique is cheap and allows the self-construction, the bricks vary largely in shape, strength and durability. This leads to weak houses which suffer important damage during floods and seismic events. A solution which has been proposed in the last decades is the use of drystack masonry with stabilized interlocking compressed earth blocks (ICEB). These blocks are manufactured by compacting cement stabilized earth in a manual or hydraulic press into a mould and then air cured for 28 days. The resulting blocks present uniform shapes, higher values of strength and durability and lower embodied energy than the traditional bricks. The material properties of ICEBs has been researched extensively, but little has been concluded with respect to the structural behaviour of these masonry dry-stack systems. Motivated by the above reasons, this work focused on the study of ICEBs to be used in dry-stack masonry of one storey houses in regions with moderate seismicity. Malawi was selected as the case study country. The mechanical characterization of the masonry was made by first studying the material properties of the blocks. Parameters such as compression and flexural strength, the Young’s modulus and compressive and tensile fracture energy have been determined through laboratory tests. In a second phase, masonry specimens were tested to determine the compressive strength, shear behaviour of the dry joints and shear behaviour of full scale walls. Finally, to study the behaviour of a real structure under seismic action, a small masonry mock-up of a house was tested on a shaking table. The results of the tests showed that it is possible to produce ICEBs of sandy soils with sufficient strength. The tests of shear walls revealed that the shear strength of this masonry is low, but comparable to that of other earthen walls. The walls also showed high values of ductility and behaviour factor. The shaking table test showed that the mock-up resisted without significant damage peak ground accelerations (PGA) of 0.2 g, which are equivalent to those expected for frequent earthquakes in Malawi. It also showed that moderate damage can be expected for rare earthquakes with PGAs of 0.3 g and that near collapse would occur at almost twice that value. The behaviour factor was of 1.5, which is the maximum permitted by the Eurocode 8 for unreinforced masonry. The knowledge gained in the several phases of this work was used to develop a manual for building ICEB houses.
A terra tem sido usada como material de construção para a edificação de casas em África. Uma das técnicas mais comuns é a alvenaria de tijolos de terra, secos ao sol ou cozidos em forno, com argamassa de terra. Embora esta técnica seja barata e permita a auto-construção, os tijolos variam muito de forma, resistência e durabilidade. Isto leva a casas de fraca qualidade, que sofrem danos importantes em caso de inundação ou evento sísmico. Uma solução que tem sido proposta nas últimas décadas é a alvenaria de blocos de terra compactada com sistema de encaixe (ICEB). Estes blocos são produzidos por compactação de terra estabilizada com cimento numa prensa manual ou hidráulica e são deixados a curar ao ar. Os blocos resultantes apresentam formas uniformes, valores de resistência e durabilidade superiores e energia incorporada mais baixa que os tijolos tradicionais. As propriedades dos ICEBs tem sido investigada intensivamente, mas pouco tem sido concluído em relação à definição do comportamento estrutural destes sistemas de alvenaria de junta seca. Motivado pelas razões acima expostas, este trabalho focou-se no estudo de ICEBs para serem utilizados em alvenaria de junta seca de casas com um andar em regiões de sismicidade moderada. O Malawi foi o país escolhido como caso de estudo. A caracterização mecânica da alvenaria foi conseguida estudando-se primeiro as propriedades materiais dos blocos. Foram determinadas experimentalmente várias propriedades mecânicas, tais como resistência à compressão e flexão, módulo de elasticidade, e energia de fratura em compressão e tração. Numa segunda fase, foram ensaiados provetes de alvenaria para caracterizar-se a resistência à compressão, comportamento ao corte das juntas secas e comportamento de corte de paredes à escala real. Finalmente, um pequeno modelo de uma casa foi ensaiado em mesa sísmica para se estudar o comportamento de uma estrutura real sob ação sísmica. Os resultados dos ensaios mostraram que é possível produzir ICEBs com resistência suficiente, a partir de solos arenosos. Os ensaios das paredes à escala real revelaram que a resistência ao corte da alvenaria é baixa, mas comparável à de outras paredes de terra. As paredes também apresentaram valores elevados da ductilidade e do fator de comportamento. O ensaio de mesa sísmica mostrou que o modelo resistiu sem danos significativos a acelerações pico do solo (PGA) de 0.2 g, que são equivalentes às esperadas em sismos frequentes no Malawi. Também se mostrou que podem ser esperados danos moderados para sismos raros com PGAs de 0.3 g e que o quase colapso só ocorreria para cerca de o dobro deste valor. O fator de comportamento foi de 1.5, que é o máximo permitido pelo Eurocódigo 8 para alvenaria não reforçada. O conhecimento obtido das várias fases deste trabalho foi utilizado para se desenvolver um manual para a construção de casas de ICEBs.
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Gomes, Diogo Dias. "Construção sustentável em blocos de terra compactada". Master's thesis, 2012. http://hdl.handle.net/1822/29575.
Texto completo da fonteResumo:
Dissertação de mestrado integrado em Engenharia CivilAtualmente presume-se que aproximadamente metade da população mundial habite em edifícios construídos em terra. A técnica BTC (Blocos de Terra Compactada), blocos obtidos através da mistura de terra água e cimento que após compressão e cura poderão ser utilizados na construção. A conjuntura económica atual visa cada vez mais a procura de novas técnicas eficazes que apresentem vantagens económicos elevados. A presente dissertação é desenvolvida no seguimento do interesse manifestado por uma empresa nacional, Mota-Engil S.A., para desenvolver uma manual de autoconstrução de edifícios habitacionais mistos sustentáveis com blocos de terra compactada (BTC), neste caso no Malawi, pois apresenta condições climatéricas adequadas a esta técnica. Nesta dissertação serão exemplificados e justificados todo o processo de técnica e construção, desde a fabricação dos blocos até às fases que integram a construção integral das habitações. Por fim, efetua-se uma escolha da forma, incluindo a mascote, e a apresentação do conteúdo do manual.
Currently it is assumed that approximately half the world's population lives in buildings constructed of earth. The technique CEB (compressed earth blocks) is obtained by mixing water, soil and cement that after curing and compression can be used in construction. For the developing countries, the current economic environment is increasingly targeting the search for new effective techniques that have high economic advantages. This thesis was developed following the interest expressed by a national construction company, Mota-Engil S.A. to develop a manual for self-construction of residential buildings with CEBs, in this case in Malawi, because it presents climatic conditions suitable for this technique. This thesis will exemplify and justify the entire construction technique and is process, since the manufacture of the blocks up to the phases that comprise the housing construction . Finally, it makes up a choice of form, including the mascot, and the presentation of the contents of the manual.
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Gontijo, Guilherme Lopes. "Thermal behaviour of compressed earth blocks with municipal organic waste incorporation". Master's thesis, 2018. http://hdl.handle.net/10198/22533.
Texto completo da fonteResumo:
Mestrado de dupla diplomação com o Centro Federal de Educação Tecnológica Celso Suckow da Fonseca - Cefet/RJConstruction sector is one of the largest consumers of natural resources among human activities. Over the last years, with the increasingly interest for sustainable practices, the use of earth as a raw construction material re-emerged as a feasible way to reduce environmental impacts. In this scenario, compressed earth blocks (CEBs) arose as a construction technique with large sustainable potential, once they do not require cooking processes on their manufacture and due to the possibility of incorporation of fibres and wastes. This work aims to evaluate the incorporation of the organic fraction of municipal waste on CEBs, through its thermal properties and behaviour when subjected to fire situations. For such, a preliminary characterization of the CEBs to determine their porosity and bulk density was held. Subsequently, an evaluation of chemical aspects of the CEBs and its components was performed through thermogravimetric analyses. Thermal properties of the blocks were also calculated using transient methods. Finally, a CEBs panel was tested experimentally to evaluate criteria of integrity and insulation, and numerical simulations were held to provide a better understanding towards this phenomenon. The obtained results indicate that the incorporation of organic waste does not affect the capability of CEBs walls to accomplish fire safety criteria. Furthermore, the incorporated CEBs thermal properties still accomplish the minimums required by the standards and may also allow to reduce the heat transfer through building envelopes, which emphasize the sustainable feature of the blocks.
A construção civil é um dos setores de maior consumo de recursos naturais entre as atividades humanas. Nos últimos anos, com o crescente interesse por práticas sustentáveis, o uso de terra como matéria-prima construtiva ressurgiu como uma maneira viável de reduzir impactos ambientais. Nesse cenário, os blocos de terra compactados (BTCs) surgiram como uma técnica de construção com grande potencial sustentável, uma vez que não requerem processos de cozimento em sua fabricação e devido à possibilidade de incorporação de fibras e resíduos. O presente trabalho tem como objetivo avaliar a incorporação da fração orgânica de resíduos urbanos em BTCs, por meio de suas propriedades térmicas e comportamento quando submetido a situações de incêndio. Para tal, foi realizada uma caracterização preliminar dos BTCs para determinar sua porosidade e densidade aparente. Posteriormente, foi realizada uma avaliação dos aspectos químicos dos BTCs e seus componentes por meio de análises termogravimétricas. As propriedades térmicas dos blocos também foram calculadas usando métodos transientes. Finalmente, um painel feito em BTCs foi testado experimentalmente para avaliar os critérios de integridade e isolamento quando submetido a incêncios, e simulações numéricas foram realizadas para fornecer uma melhor compreensão desse fenômeno. Os resultados obtidos indicam que a incorporação de resíduos orgânicos não afetam a capacidade das paredes de BTCs em cumprir os critérios de segurança contra incêndio. Além disso, as propriedades térmicas dos BTCs com resíduo incorporado cumprem ainda os mínimos exigidos pelas normas e também podem permitir reduzir a transferência de calor através das envoltórias da construção, o que enfatiza a característica sustentável dos blocos.
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FCeesay, Isatou, e 伊莎圖. "Effect of OMRS on the Physical Properties of Compressed Stabilized Earth Blocks". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/54349847169742792172.
Texto completo da fonteResumo:
碩士國立成功大學
土木工程學系
102
Earth blocks are generally brittle, weak and vulnerable to damage. Cement and lime have been used as a stabilizing agent to improve the compressive strength and water absorption capacity of compressed stabilized earth blocks (CSEB) and also make them suitable for construction. Stabilizers are usually blended with industrial by-products to enhance the engineering properties as well as to get rid of waste. In Taiwan, the disposal of reservoir sludge has become a big issue. The reservoir sludge, mainly consisting of smectite clay, is organomodified by a cationic exchange reaction and becomes hydrophobic. This research outlines the results of an experimental study to assess the effects of Organo -Modified Reservoir Sludge (OMRS) on Compressed Stabilized Earth Blocks (CSEB). Earth blocks Stabilized with various percentage of Lime-OMRS, Cement-OMRS and plain Cement were produced and tested for compressive strength and water absorption tests. Experimental results reviled that the optimal dosage of OMRS for Cement-OMRS stabilizer is 3% and for Lime-OMRS stabilizer is 1% by weight. OMRS powders served as fine aggregates were as filled in the void spaces to create a denser CSEB which leads to higher compressive strength and lower water absorption value compared to that of plain cement stabilizer.
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EVANDER, RICHARD, e RICHARD EVANDER. "A Hybrid Deep Machine Learning Model For Soil Classification of Compressed Earth Block". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9x3u39.
Texto completo da fonteResumo:
碩士國立臺灣科技大學
營建工程系
107
Classifying or predicting soil type for Compressed Earth Block (CEB) construction using machine learning model is an important technique to replace laboratory tests which are time and cost consuming. The previous study has established soil classification using Artificial Neural Network (ANN). Nonetheless, gradient-based learning on ANN face several issues like overfitting and trapped in local minima due to poor generalization performance. In the further development of the neural network model, Extreme Learning Machine (ELM) has been developed with faster learning speed and better generalization performance compared to ANN. However, ELM itself has some drawbacks in random input weights and heavy memory problems. This research proposed the model called Backpropagated Deep Restricted Boltzmann Extreme Learning Machine (BD-RBELM) which establish deep ELM network to solve the heavy memory problem and use Restricted Boltzmann Machine (RBM) to train input weight for solving random input weights problem. The model then used for the soil classification problem with the final performance of 95.144% accuracy and 95.120 F1-Score, which performed better compared with the other AI techniques.
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Rix, Carl Gunther. "Stabilisation of a highly plastic clay soil for the production of compressed earth blocks". Thesis, 2014.
Encontre o texto completo da fonteResumo:
Clay plays an important role in the suitability of soil for use in construction. The
affinity of a clay for moisture makes it susceptible to shrinkage and swelling on
drying and wetting and therefore problematic in terms of construction, where
stability is required for the integrity of a structure to remain intact. It is therefore
important to have methods of dealing with problematic clays in order to allow
clays to be used as a construction material. One of the methods is known as soil
stabilisation, where the properties of a soil and mainly the clay fraction are
altered to make it more suitable for its intended purpose.
The thesis investigates the use of a highly plastic clayey soil for the production
of building blocks. Due to the clayey nature and its associated properties the soil
it is not suitable in its natural state. Soil stabilisation is investigated as a method
to alter the properties of the soil. The principles of soil stabilisation are presented
as an introduction to the laboratory testing programme.
Combinations of lime, cement and fly ash are investigated as a stabilising agent.
They are investigated to determine which combination alters the properties of the
soil to such an extent, that a compressed soil block produced using the
combination and the clayey soil, would perform satisfactorily according to
accepted standards. Combinations were designed so that comparisons could be
made between blocks to determine what effect the addition of a certain stabilising
agent would have on the performance of the block in terms of the tests
conducted.
The engineering properties of the untreated soil which are not considered
suitable for use in compressed soil blocks, are significantly enhanced by he
addition of the stabilising agents. The test conducted on the blocks indicate that
the addition of 4% lime, 20% fly ash and 7% cement added to the soil produces a
block that satisfies the criteria adopted for the research and that are generally in
accord with international standards.
A mineralogical analysis was also undertaken in an attempt to identify changes in
the mineralogy of the soil, and particularly the clay, as a result of the addition of
the three stabilising agents. This analysis was done using x-ray diffraction. Due
to the nature of the clay mineral and possibly the poor crystal structure thereof,
the results were disappointing. No significant change in the clay was observed to
correlate with the results of the improved performance as indicated by the
physical tests.
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"Experimental Study of Cement Stabilized Fiber Reinforced Compressed Earth Blocks as an Alternative Building Material". Master's thesis, 2016. http://hdl.handle.net/2286/R.I.41266.
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abstract: Concern and interest about the environment and ecologic systems have promoted the usage of earth as a construction material. Technology advancement has resulted in the evolution of adobe into compressed stabilized earth blocks (CSEB). CSEB’s are prepared by compressing the soil-stabilizer mixture at a particular stress. In order to accomplish the required strength, cement has been used in a regular basis as stabilizing agent. It is of interest to find means to reduce the cement used in their construction without affecting its dry strength and durability. In this study, natural fibers were used along with lower proportions of cement to stabilize soil with varying fine content. Blocks were compacted at 10MPa stress and prepared by using 7%, 5% and 3% cement along with fiber content ranging from 0.25% to 2%. The effect of fine content, cement and fibers on strength and durability of the CSEB blocks were studied. Different sand/fine fractions of a native Arizona soil were used to fabricate the blocks. Results indicate that the compressive strength reaches a maximum value for blocks with 30% fine content and inclusion of fibers up to 0.5% increased the dry compressive strength. The use of 0.25% fiber by weight and 5% cement content showed comparable dry compressive strength to that of the 7% cement blocks with no fibers. The dry strength of the blocks reached an optimal condition when the combination of materials was 30% fines, 5% cement and 0.5% fibers, which satisfied the strength requirement given by the ASTM C62 and ASTM C216 standards for construction material. The CSEB’s with 0.5% fiber had higher toughness. The durability was determined by subjecting the CSEBs to wetting and drying cycles. The blocks with 5% cement withstand the durability test as the dry strength was higher than that required for construction use.
The blocks were also submitted to heating and cooling cycles. After 12 cycles, the specimens showed a reduction in strength, which further increased as the number of cycles increased. Finally, the thermal resistivity of fiber reinforced CSEB was found to be higher than that for clay bricks.Dissertation/Thesis
Masters Thesis Civil and Environmental Engineering 2016
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Carvalho, Manuel Augusto Barbosa. "Desenvolvimento e validação de uma solução construtiva em BTC". Master's thesis, 2015. http://hdl.handle.net/1822/40558.
Texto completo da fonteResumo:
Dissertação de mestrado integrado em Engenharia CivilA construção em terra é uma técnica utilizada em todo o mundo e uma das formas de construção mais antigas. Este material apresenta diversas vantagens comparadamente com outros materiais existentes para a construção. Uma das técnicas mais desenvolvidas atualmente é a técnica de construção com blocos de terra compactada (BTC). A utilização da construção em BTC é uma melhoria da técnica de adobe e consiste em compactar mecanicamente terra num molde para diminuir a sua porosidade e aumentar a resistência mecânica, originando um bloco. Uma das principais desvantagens é a diminuta adequabilidade dos solos disponíveis localmente. No caso de solos residuais graníticos da região do Minho, a sua adequabilidade é quase inexistente, sendo preciso efetuar a estabilização química do solo, sendo o mais usual a adição de cimento e cal. Assim neste trabalho foi importante caracterizar o solo para posteriormente estabiliza-lo e produzir BTC. De forma a dar continuidade a trabalhos realizados anteriormente e trabalhos realizados em simultâneo com este, realizou-se uma caracterização mecânica dos BTC. Seguidamente foram ensaiados prismas e paredes de alvenaria à compressão uniaxial para avaliar a influência de argamassa presente nas juntas horizontais. Paralelamente com estes ensaios, foram realizados ensaios à compressão em paredes de alvenaria em BTC com dois tipos de reforços distintos e separadamente que se podem aplicar neste tipo de construção, de modo a avaliar o seu efeito.
Earth construction is a technique used worldwide and one of the oldest construction forms. This material has several advantages when compared with other existing construction materials. One of the most developed technique currently is the use of compressed earth blocks (CEB). The use of CEB is an improvement of the ancient adobe technique and consists in mechanically compacting soil inside a mould to reduce its porosity and improve the mechanical strength, resulting into an earth block. A major disadvantage is the diminished suitability of locally available soils. In the case of residual granitic soils of the Minho region, its suitability is almost non-existent, making necessary the use of some sort of chemical soil stabilization, being the most usual the addition of cement and lime. Thus this work it became important to characterize the soil to further stabilize it and produce CEBs. In order to further develop the work carried out previously and to consider the work carried out simultaneously by others with this research work, a deep mechanical characterization of CEBs was carried out. Afterwards, the blocks were tested together with masonry walls under uniaxial compression to evaluate the influence of the horizontal mortar joints. In parallel with these tests, compression tests were performed on masonry wallets considering two different types of strengthening techniques that can be applied in this type of construction, in order to evaluate its effect.
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"The development of a standard of care defining suitable testing of geomaterials intended for unstabilized compressed earth block construction". UNIVERSITY OF COLORADO AT BOULDER, 2009. http://pqdtopen.proquest.com/#viewpdf?dispub=1464558.
Texto completo da fonte
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Grunert, Brett Ryan. "The development of a standard of care defining suitable testing of geomaterials intended for unstabilized compressed earth block construction". Thesis, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1464558.
Texto completo da fonte
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Simões, Liliana Sofia da Silva. "Comportamento acústico de blocos de terra compactada ativados alcalinamente". Master's thesis, 2015. http://hdl.handle.net/1822/40664.
Texto completo da fonteResumo:
Dissertação de mestrado integrado em Engenharia CivilAo longo dos anos, a construção em terra, tem vindo destacar-se tanto na engenharia civil como a nível arquitetónico. As vantagens são muitas quando comparada com outras soluções construtivas convencionalmente utilizadas nos países desenvolvidos, que se baseiam na utilização de betão armado e alvenaria de tijolo cozido. Existem diferentes técnicas de construção em terra, contudo, o adobe é ainda a mais popular e a mais utilizada. Com a grande necessidade de se encontrar materiais e técnicas sustentáveis, o uso de bloco de terra compactada (BTC) está a tornar-se cada vez mais conhecido. É uma técnica relativamente recente e a produção consiste em compactar mecanicamente a terra num molde para que assim se diminua a porosidade e aumente a resistência. Contudo, é uma técnica com algumas limitações, como a diminuta adequabilidade dos solos disponíveis no local. Resultados obtidos por estudos anteriores com solos residuais graníticos da região Minho, ativados alcalinamente por cinzas volantes, são bastantes satisfatórios a nível de resistência dos blocos. Nesta dissertação pretende-se avaliar experimentalmente o comportamento acústico de blocos de terra, com solo residual granítico do Minho, compactada e estabilizada com recurso à ativação alcalina de cinzas volantes. A aplicação desta técnica (relativamente recente) ao desenvolvimento de BTCs é inovadora e espera-se que os resultados possam demonstrar o potencial de sustentabilidade da mesma e de adequação às exigências mínimas de isolamento acústico definidas nos Regulamentos e nas Normas de Desempenho Acústico dos Edifícios.
Over the years, the earth construction, has a distinguished both in civil engineering, such as architectural level. There are many advantages when compared with other constructive solutions conventionally used in developed countries, which rely on the use of reinforced concrete and brickwork cooked. There are different construction techniques in earth, however, adobe is still the most popular and most used. With great need to find sustainable materials and techniques, the use of compressed earth block (BTC) are becoming increasingly well known. It is a relatively recent technique, and the production is to mechanically compact the soil into a mold to thereby decrease the porosity and increase strength. However, it is a technique with some limitations, such as reduced suitability of the soil on site. Results of previous studies with granitic residual soils of the Minho region, alkali-activated by fly ashes, are quite satisfactory to the blocks resistance level. This dissertation aims to experimentally evaluate the acoustic behavior of earth blocks, with granitic residual soil of Minho, compacted and stabilized using the alkaline activation of fly ashes. The application of this technique (relatively recent) at the developing of BTC’s is innovative and it is expected that the results can demonstrate the potential sustainability of the workstation and adaptation to the minimum requirements of sound insulation defined in the Regulations and in the buildings Acoustic Performance Standards.
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Oliveira, Juliana Vieira. "Comportamento mecânico de blocos de terra compactada ativados alcalinamente". Master's thesis, 2014. http://hdl.handle.net/1822/36265.
Texto completo da fonteResumo:
Dissertação de mestrado integrado em Engenharia CivilA construção em terra está presente em todo o mundo e representa uma das formas de construção mais antigas. Apresenta várias vantagens a nível económico, social e ecológico, sendo ainda muito versátil na medida em que permite a utilização de muitas técnicas diferentes, entre elas a construção com alvenaria de blocos de terra compactada (BTC). A utilização de BTC é relativamente recente, e a sua produção consiste em compactar mecanicamente terra num molde para diminuir a porosidade e aumentar a resistência do material de terra resultante. No entanto, uma das principais limitações da construção em terra é a diminuta adequabilidade dos solos disponíveis localmente. No caso dos solos residuais graníticos da região do Minho (Portugal), a sua adequabilidade é praticamente inexistente, e o seu uso requer estabilização. Assim, estudos anteriores avaliaram a possibilidade de produzir BTC com solo residual granítico do Minho, estabilizado através da ativação alcalina de cinzas volantes. Os resultados obtido foram muito satisfatórios, uma vez que conseguiram atingir níveis de resistência dos blocos, muito superiores aos impostos pelas normas existentes, demonstrando, assim, o potencial da técnica. Este trabalho pretende dar desenvolvimento à investigação mencionada anteriormente. Assim, efetuouse uma caracterização mecânica dos BTC ao longo da idade de cura, e foram desenvolvidas duas argamassas de terra para o assentamento em alvenaria, também estas estabilizadas através da ativação alcalina de cinzas volantes. Depois disto, foram efetuados ensaios de compressão (prismas e paredes) de corte (prismas) de alvenaria de BTC. De forma a avaliar a influência das argamassas no comportamento deste tipo de alvenaria, foram construídos e ensaiados prismas e paredes com junta seca e com cada uma das argamassas desenvolvidas. Os resultados obtidos permitiram conhecer a evolução da resistência dos BTC com o tempo de cura, compreender o comportamento da alvenaria de BTC sujeitos a esforços de compressão e de corte, e compreender a influência das argamassas de assentamento neste tipo de alvenaria.
Earth construction is world-wide spread and constitutes one of the most ancient solutions for building. It presents several advantages at the economic, social and ecological level, and also it is very adaptable, since it offers the use of many different techniques, including the construction with masonry of compressed earth blocks (CEB). The use of CEB is relatively recent, and their production consists in compacting mechanically earth in a mould to reduce the porosity and to increase the strength of the resulting earthen material. However, one of the main limitations of earth construction is the low suitability of the available soils at the site. In the case of the residual granitic soils from Minho region (Portugal), their suitability is practically nonexistent, and its use requires stabilisation. Thus, previous research evaluated the possibility of producing CEB with residual granite soil from Minho stabilised with alkaline activation of fly ash. The results obtained were very satisfactory, since it was possible to achieve strength levels much higher than those demanded by existing standards, demonstrating the high potential of this technique. This work aims at developing the aforementioned research. Thus, the mechanical characterization of CEB with the curing time was performed and two earth mortars also stabilised by alkaline activation of fly ash were developed for use in bed joints. Then, compression (prisms and wallets) and shear (prisms) tests were carried out on masonry specimens made with CEB. Masonry prisms and wallets with dry-stack joints and joints mortared with the two developed mortars were built and tested in order to assess the influence of the mortar on the behaviour of this type of masonry. The results obtained allowed assessing the evolution of the strength of the CEB with the curing time, understanding the behaviour of masonry made with CEB under compression and shear loads, and understanding the influence of the bed joint mortars in this type of masonry.
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Lopes, Carlos Eduardo de Almeida Andrade. "Desenvolvimento e validação de um sistema construtivo estrutural em BTC". Master's thesis, 2017. http://hdl.handle.net/1822/70578.
Texto completo da fonteResumo:
Dissertação de mestrado integrado em Engenharia CivilA terra enquanto material de construção tem sido utilizada há milhares de anos, devido às propriedades únicas que possui. Entre as técnicas construtivas que este material permite, encontram-se os blocos de terra comprimida (BTC). Os BTC têm ganho relevância nos últimos anos, pois possuem vantagens que os distinguem das restantes técnicas de construção em terra. No entanto, a sua utilização nos países industrializados ainda é residual. Entre os motivos que levam a que isto aconteça, destaca-se a baixa capacidade resistente das construções, quando comparada aos materiais tradicionais, especialmente no que diz respeito às ações sísmicas. Este trabalho pretende dar continuidade às investigações que têm sido desenvolvidas na Universidade do Minho no que diz respeito à caracterização mecânica de elementos estruturais de BTC, com o objetivo de avaliar e melhorar a resistência de estruturas feitas com recurso a este material. Com isso em vista, foi realizada uma campanha experimental que envolveu diferentes ações e configurações construtivas: ensaios de compressão e flexão em unidades de BTC, ensaios de compressão uniaxial em prismas e ensaios de compressão uniaxial e diagonal em paredes de referência e paredes reforçadas com reboco armado e varões de aço embebidos em argamassa.
Earth as a building material has been used for thousands of years, due to its unique properties. Among the construction techniques that this material allows, one can find compressed earth blocks (CEB). CEB have gained a certain relevance over the last few years, since they have advantages that set them apart from the other earth building techniques. However, their use in industrialised countries is still not widespread. Among the reasons that justify this, there is the low resistant capacity of CEB-constructions when compared to traditional materials, specially in respect to seismic actions. This work aims to further continue the studies that have been made at University of Minho, Portugal, in regards to the mechanical characterisation of structural elements of CEB, in order to evaluate and improve the strength of structures made with this material. With that in mind, an experimental campaign has been carried out, which involved different actions and construction setups: compression and bending tests in CEB units, uniaxial compression tests in prisms and uniaxial and diagonal compression tests in both reference walls and in walls reinforced with reinforced render and steel bars soaked in mortar.
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Machado, Gilberto Carlos Salazar. "Caracterização experimental das propriedades físicas e mecânicas e da durabilidade de blocos de terra comprimida". Master's thesis, 2019. http://hdl.handle.net/1822/71178.
Texto completo da fonteResumo:
Dissertação de mestrado integrado em Engenharia CivilA terra tem vindo a ser usada há mais de onze milénios e continua ainda hoje a ser o material de construção mais difundido em todo o mundo. Contudo, com o aparecimento de outros materiais de construção (betão, aço e tijolo cerâmico), a construção em terra caiu em desuso. No entanto, a terra, como material de construção, apresenta diversas vantagens no que se refere ao seu custo, à sua capacidade de isolamento térmico e acústico, à sua baixa energia incorporada (associada à fases de extração, transformação, transporte e produção) e a produção de resíduos é praticamente insignificante. Dada a grande preocupação existente na atualidade sobre a sustentabilidade, a construção em terra assume-se como sendo uma alternativa para o setor de construção. Existem diversas técnicas de construção em terra, sendo os blocos de terra comprimida (BTC) a técnica construtiva mais aceite pela sociedade, pois consegue-se um maior controlo de qualidade durante o seu processo de construção. Assim sendo, a presente dissertação tem como principal objetivo caracterizar o comportamento de blocos de terra comprimida, que se encontram atualmente no mercado, sendo utilizados para a execução de alvenaria de compartimentação. Para tal, foi caracterizado o solo utilizado no fabrico dos BTC (análise granulométrica, ensaio de compactação: Proctor, limites de consistência, determinação do teor de finos através do ensaio de azul de metileno e equivalente de areia) e foram caracterizadas as propriedades mecânicas, físicas e de durabilidade dos BTC (resistência à compressão, resistividade elétrica, velocidade de propagação dos ultrassons, absorção de água por imersão, absorção de água por capilaridade e erosão à chuva). Após análise dos resultados, obtidos na campanha experimental, conclui-se que o solo caracterizado é um solo com características adequadas para ser utilizado no fabrico dos BTC. Os BTC caracterizados apresentam uma boa resistência à compressão, podendo ser usados com função estrutural. Apresentam, no entanto, grande sensibilidade à água, já era de esperar pois o fabricante recomenda que os mesmos não sejam aplicados em elementos expostos à chuva sem a devida proteção.
The earth has been used as a building material for over than eleven thousand years and is still today the most widespread building material in the world. However, with the development of other building materials (e.g. concrete, steel and ceramic brick), the use of earth for construction has fallen into disuse. However, earth as a building material has several advantages with regard to its cost, its thermal and acoustic insulation characteristics, the insignificant amount of waste produced in the construction processes, its low embodied energy (energy related to the following life cycle stages: extraction, transformation, transportation and production). Additionally, given the current high demand for sustainability, earth construction is assumed to be an alternative to the construction sector. There are several techniques for earth construction like the compressed earth blocks (CEB). CEB is one of the most society’s accepted earth construction technique, since it allows for a better quality control during the construction process. Therefore, the present dissertation aims to characterize the behaviour of a CEB which is now already used in the market, being used for the construction of partitioning masonry. To this end, the soil used in the CEB production was characterised, including: particle size distribution, Proctor compaction test, consistency limits, determination of fines content by a methylene blue test and sand equivalent. Additionally, the CEB mechanical, physical and durability properties were also characterised, including: compressive strength, electrical resistivity, ultrasonic pulse velocity, water absorption by immersion and capillary water and rain erosion. After analysing the results obtained in the experimental campaign, it is concluded that the soil has suitable characteristics to be used in the production of CEB. The characterized CEB exhibit good compressive strength and can be used both as a non-loadbearing and a loadbearing wall, and mainly in a partition wall. Nevertheless, CEBs have low resistance to water, what was expected since as the recommendation of the manufacture they can only be used in an external element if implementing an adequate water protection measure.
Apoio concedido pelos fundos do FEDER através do Programa Operacional de Competividade e Internacionalização (POCI) e pelos fundos nacionais através da FCT- Fundação para a Ciência e Tecnologia no âmbito do projeto com a seguinte referência POCI-01-0145-FEDER-029328, que foi fundamental para o desenvolvimento deste estudo.
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Silva, Luís Carlos Ferreira. "Produtos de alteração de rochas para construções em terra". Master's thesis, 2018. http://hdl.handle.net/1822/65089.
Texto completo da fonteResumo:
Dissertação de mestrado em Geociências (área de especialização em Valorização dos Recursos Geológicos)A construção em terra é uma técnica bastante antiga que remonta ao início da própria humanidade. Se bem que atualmente seja menos popular, pelo menos em Portugal. A promoção deste modo de construção pode ter interesse do ponto de vista ambiental, não só em termos de minimização de consumo de recursos e de emissões de poluentes, mas também na perspetiva de valorização de resíduos. Estudaram-se produtos de alteração in situ de rochas com preservação da textura (saprólitos, que podem ser considerados como solos em termos de Engenharia - solos residuais) de granitos (dois biotíticos e dois leucocráticos) e de rochas metassedimentares silicatadas (três do Silúrico e uma do Devónico). Os locais de amostragem situaram-se nos concelhos de Barcelos (1), Braga (5), Póvoa de Varzim (1) e Vila Nova de Famalicão (1). Realizaram-se nos solos estudos mineralógicos por difração de raios-X de preparações orientadas da fração inferior a 2 μm e ensaios físicos (granulometria e ensaio de azul de metileno). Prepararam-se provetes moldados de solo e com mistura deste com cimento Portland (4%, 8% e 12 %) para ensaios de absorção de água (capilaridade e imersão) e de resistência à compressão uniaxial. Estes últimos selecionaram dois solos (um produto de alteração de granito biotítico e um produto de alteração de rochas metamórficas) que apresentaram os valores mais elevados. A análise de componentes principais sugere que poderão existir combinações de variáveis que separam os mesmos (dos outros solos estudados). Estes dois solos foram utilizados para produzir blocos com misturas de solo e cimento, onde foram avaliados à resistência à compressão e ao ensaio de erosão acelerada por simulador de chuva com resultados considerados adequados para a construção com terra. Ainda que os produtos de alteração in situ selecionados possam não ser objeto de um aproveitamento comercial próprio, os resultados obtidos sugerem formas de aproveitar os mesmos na perspetiva de valorização de resíduos de desmonte (lamas, solos de cobertura entre outros).
Construction with earth is a very old technique that goes back to the beginning of civilization itself. Although it is currently less popular, at least in Portugal, the promotion of this mode of construction may be interesting from an environmental point of view, not only in terms of minimizing resources consumption and pollutants emissions, but also in the perspective of waste recovery. In the present work were studied in situ alteration products of rocks with texture preservation (saprolites, which can be considered as engineering soils - residual soils) of granites (two biotitic and two leucocratic) and silicate metasedimentary rocks (three of Silurian age and one of Devonian age). Sampling sites were located in the counties of Barcelos (1), Braga (5), Póvoa de Varzim (1) and Vila Nova de Famalicão (1). On these soils were performed mineralogical studies (by X-ray diffraction of oriented preparations) and physical tests (granulometry and methylene blue test). Moulded samples of soil and soil with Portland cement (4%, 8% and 12%) were prepared for water absorption tests (capillary and immersion) and uniaxial compression strength tests. The latter highlighted two soils (the alteration product of a biotitic granite and the alteration product of a metamorphic rock) that showed the highest values. A principal component analysis suggests that there may be combinations of variables that explain the better results of these soils (in relation to the other soils studied here). These two soils (with higher strength) were used to produce blocks with mixtures of soil and cement. Compressive strength tests and accelerated erosion tests (by rain simulation) were performed on these blocks with results that were considered suitable for earth constructions. Although the studied in situ alteration products may not be viable commercial building material on their own, the results suggest ways for their valorization in the perspective of waste recovery.
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Coelho, Rui Eduardo Fernandes. "Avaliação do desempenho acústico e na presença do fogo de BTC". Master's thesis, 2019. http://hdl.handle.net/1822/71213.
Texto completo da fonteResumo:
Dissertação de mestrado integrado em Engenharia CivilO trabalho de dissertação que se apresenta assenta na construção em terra. Numa fase inicial, a investigação sobre a construção em terra, apresenta caraterísticas de se estar a ensaiar processos e técnicas fundamentais para o crescimento da sustentabilidade no setor da construção. As vantagens do recurso à terra para construção são inúmeras, nomeadamente a acessibilidade, pois é um produto natural e existente no solo e também por ser um processo de construção com impacto na diminuição da pegada ecológica. Sendo assim, esta construção tem vindo a conquistar progressivamente o mercado da construção civil, em diversos países, sendo que há maior procura dos processos de construção com este material e na industrialização da produção, em países mais desenvolvidos. Há várias técnicas na construção em terra e a escolhida para este trabalho foi o bloco de terra compactada (BTC). É uma técnica que se apresenta com perspetiva de aceitação pelas sociedades atuais e também porque parece permitir a padronização dos blocos, um maior controlo de qualidade no seu processo de produção com uma boa capacidade de resistência. Há igualmente muitas incertezas funcionais e normativas que impõe barreias à aceitação desta técnica. Assim, este estudo apresenta ensaios experimentais de caraterização acústica e de caraterização do comportamento dos BTC ao fogo, numa tentativa de poder aferir a funcionalidade dos blocos de terra comprimida (BTC), na sua componente acústica e de resistência ao fogo. Releva-se igualmente com este estudo, a importância de aumentar o conhecimento da técnica construtiva – BTC proposta a estudo, por se apresentar como um dos possíveis mecanismos da bioconstrução, de forma a ser atingida a resiliência ambiental.
This work is based on a growing motivation for building with earth. The curiosity for the investigation of the construction with earth is assumed by the possibility of testing processes and techniques which are fundamental for the growth of sustainability in the construction sector. The benefits resulting from the use of earth material in construction are innumerable in terms of its capability and availability as well as its impact on the ecological footprint. Thus, this method has been progressively conquering the civil construction market in several countries, namely in the so called developed ones where there has been a greater demand for construction processes with this material and in the production industrialization. There are several techniques in earth construction and the one chosen for this paper was the compressed earth block (CEB). It is a technique that presents itself with prospect of acceptance by current societies and it seems to allow the standardization of the blocks, a greater quality control in their production process, with a good strength capability. However, there are also many functional and normative uncertainties that impose barriers to the acceptance of this technique. This study is based on experimental tests on acoustic characterization and on the CEBs reaction to fire. It is also intended with this study, to increase the knowledge on the referred building technique - CEB, as it presents itself as one of the possible mechanisms of bioconstruction, so that environmental resilience can be achieved.
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Araújo, Maria Helena de. "Comportamento térmico de blocos de terra comprimida ativados alcalinamente". Master's thesis, 2015. http://hdl.handle.net/1822/40662.
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Dissertação de mestrado integrado em Engenharia CivilA construção em terra tem vindo a ganhar uma nova expressão quer em termos arquitetónicos quer na construção civil. Esta forma de construção está presente em todo o mundo e representa uma das formas de construção mais antigas. É notória uma crescente preocupação por reinventar e renovar técnicas antigas de construção em terra, bem como das formas de melhorar a terra como material de construção. Uma vez que uma das principais limitações da construção em terra é a inadequabilidade de alguns solos disponíveis localmente, como é o caso do solo residual granítico do Minho, surge assim a estabilização dos mesmos como forma de melhorar as suas características. A construção em terra é muito versátil visto permitir a utilização de muitas técnicas diferentes, sendo a alvenaria de blocos de terra comprimida (BTC) uma das técnicas mais recentes e foi a que serviu de base para este trabalho. Neste caso, a estabilização dos BTC foi feita através da ativação alcalina de cinzas volantes. Com este trabalho pretende-se estudar o comportamento termoenergético desta nova técnica, de forma a que, em conjunto com todos os outros trabalhos já desenvolvidos ou em desenvolvimento, relacionados com os BTC com SRG, seja possível obter-se uma caracterização completa desta técnica. Assim sendo, foram efetuados testes térmicos a uma parede simples de BTC com junta seca, para caracterização da sua resistência térmica. Para que seja possível compreender a variação do comportamento termoenergético dos BTC em conjunto com outros elementos construtivos, também foram realizados ensaios térmicos numa parede simples com junta preenchida por betume e numa parede com junta preenchida por betume e com 2cm de isolamento térmico (aglomerado de cortiça) pelo exterior. Os resultados obtidos permitiram caracterizar/ calcular a resistência térmica dos BTC, assim como, compreender a variação do comportamento energético dos BTC em conjunto com outros elementos construtivos e por comparação com outras soluções construtivas correntes.
The earth construction has gained a new expression, both in architectural terms and in construction. This construction method is present throughout the world and is one of the oldest construction forms. It is evident a growing concern with reinvent and renew old building techniques in earth, as well as ways to improve the land as a building material. Since one of the main limitations of the earth construction is the inadequacy of some locally available soils, as is the case of granite residual soil of Minho, thus arises stabilization thereof in order to improve their characteristics. The earth construction is very versatile as it allows the use of many different techniques, and the masonry compressed earth blocks (BTC) one of the latest techniques and was used as the basis for this work. In this case, the stabilization of BTC was made by activation of alkaline fly ashes. This work is intended to study the thermoenergetic behavior of this new technique, so that, together with all the other work already developed or under development, related to the BTC with SRG, it is possible to obtain a complete characterization of this technique. Thus, thermal tests were performed at a single wall BTC with lute, to characterize its thermal resistance. To be able to understand the behavior of variation thermoenergetic BTC in conjunction with other construction elements, thermal tests were also performed with a single wall board filled with bitumen and a wall with gasket filled with bitumen and thermal insulation 2cm (corkboard ) from the outside. The results were used to characterize / estimate the thermal resistance of the BTC as well as understand the variation of the energy behavior of BTC in conjunction with other construction elements and by comparison with other common constructive solutions.
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Campos, André Filipe Sousa. "Desenvolvimento de uma metodologia de fabrico de blocos de terra comprimida com incorporação de materiais de mudança de fase". Master's thesis, 2021. http://hdl.handle.net/1822/74110.
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Dissertação de mestrado integrado em Engenharia CivilA construção em terra é uma técnica utilizada em todo o mundo. É uma solução que apresenta diversas vantagens quando comparada com outras soluções construtivas, nomeadamente um baixo valor de energia incorporada, bom desempenho térmico e acústico, elevada resistência ao fogo e custo relativamente baixo. Este tipo de construção é muito versátil visto permitir a utilização de muitas técnicas diferentes, sendo a alvenaria de blocos de terra comprimida (BTC) uma das técnicas mais recentes e a que serviu de base para esta dissertação. O BTC é uma melhoria da técnica de adobe e consiste em compactar mecanicamente solo em um molde para diminuir a porosidade e aumentar a resistência do material. Apesar disso, uma das limitações é a diminuta adequabilidade dos solos disponíveis localmente, surgindo assim a estabilização dos mesmos como forma de melhorar as suas propriedades. A inserção de material de mudança de fase (PCM) tem como objetivo os BTC’s armazenarem grandes quantidades de energia e dessa forma reduzir as flutuações de temperatura interior, reforçando assim o conforto térmico e reduzindo as necessidades energéticas associadas à climatização, indo assim ao encontro de uma construção que além de sustentável se tornará inovadora. De forma a dar desenvolvimento a investigações anteriores, nesta dissertação realizou-se uma campanha experimental definindo pontos importantes para diversas misturas de solo, água, cimento e PCM, tais como a caracterização do solo, a definição de uma metodologia para a incorporação de PCM nos BTC’s, as propriedades físicas e mecânicas dos blocos, e o comportamento dos BTC’s quando submetidos a diversas temperaturas.
Earht based construction is a technique used around the world. It is a solution that presents several advantages when compared to other construction solutions, namely a low value of incorporated energy, good thermal and acoustic performance, high resistance to fire and relatively low cost. This type of construction is very versatile since it allows the use of many different techniques, the masonry of compressed earth blocks (CEB) being one of the most recent techniques and the one that served as the basis for this dissertation. CEB is an improvement of the adobe technique and consists of mechanically compacting soil in a mold to decrease porosity and increase the material's resistance. In spite of this, one of the limitations is the reduced suitability of the locally available soils, thus resulting in their stabilization as a way to improve their properties. The insertion of phase change material (PCM) aims at CEB to store large amounts of energy and thus reduce fluctuations in interior temperature, thus reinforcing thermal comfort and reducing energy needs associated with air conditioning, thus meeting a construction that in addition to being sustainable will become innovative. In order to give development to previous investigations, this dissertation carried out an experimental campaign defining important points for different mixtures of soil, water, cement and PCM, such as the characterization of the soil, the definition of a methodology for the incorporation of PCM in CEB, the physical and mechanical properties of the blocks, and the behavior of CEB when subjected to different temperatures.
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Namango, Saul Sitati [Verfasser]. "Development of cost effective earthen building material for housing wall construction: investigations into the properties of compressed earth blocks stabilized with sisal vegetable fibres, cassava powder and cement compositions / by Saul Sitati Namango". 2006. http://d-nb.info/982828748/34.
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Domingues, Rui Manuel Veloso. "Avaliação do potencial económico de implementação da construção em BTC". Master's thesis, 2015. http://hdl.handle.net/1822/40651.
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Dissertação de mestrado integrado em Engenharia CivilA indústria da construção está associada a um elevado número de impactes ambientais, e o aumento do consumo de matérias-primas e energia conduziram a um aumento significativo da poluição. Assim, atualmente, as preocupações ambientais começam a surgir, dando uma resposta às necessidades do desenvolvimento de materiais, de técnicas e de métodos de construção sustentáveis que minimizem o impacte ambiental na atividade da construção. Em Portugal, o setor da construção, nomeadamente, a construção de edifícios de habitação, recorre massivamente a estruturas de betão armado e a alvenarias de tijolo cerâmico, sendo pouco recorrente a utilização de soluções construtivas em terra crua. A presente dissertação incide, essencialmente, sobre a construção em Bloco de Terra Compactada (BTC), sendo um material que reúne todas as condições para o desenvolvimento de uma construção sustentável e economicamente viável, podendo ser implementado na indústria da construção hoje em dia. Neste contexto, foi realizado um estudo do potencial de implementação e do custo desta solução construtiva, o BTC. Assim, foi concretizado um estudo comparativo para uma habitação com tipologia típica aplicando 4 diferentes soluções estruturais: a estrutura porticada de betão armado com alvenaria de tijolo cerâmico; a solução estrutural em Light Steel Framing; a solução em Madeira e a solução de paredes resistentes em BTC. Para a implementação no mercado de materiais que visam a construção sustentável, como o BTC, é necessário a abordagem de metas e exigências futuras traçadas a nível nacional, europeu e mundial. Os resultados obtidos permitiram caracterizar que o BTC é uma solução economicamente viável e sustentável em todas as fases do ciclo de vida, comparativamente aos outros tipos de soluções construtivas. Após essa análise verificou-se que o BTC corresponde a estas exigências futuras e que é possível esperar que, este tipo de material, possa ser cada vez mais utilizado.
The building industry is associated to a large number of environmental impacts, and the growing in the consumption of raw materials and energy led to significant increase in pollution. Hence, nowadays, the environmental concerns are emerging, giving an answer to the needs of materials development, techniques and sustainable construction that minimizes the environmental impacts in this activity. In Portugal, the construction sector, particularly the residential construction, uses massively reinforced concrete structures and ceramic brick masonry, seldom using building solutions in raw land. The current dissertation focuses mainly on the construction in compressed earth block (CEB), a material that meets all the required conditions for the development of a sustainable and economically viable construction and can be implemented on the present building industry. For that matter, it was performed a study about the potential implementation of this building material, the CEB. Thus, a comparative study was conducted in a house with typical typology, applying 4 different structural solutions, such as: porticoed structure of reinforced concrete with ceramic brick masonry, the structural solution in Light Steel Framing, the wood solution and the solution of resistant walls in CEB. So as to introduce in the market materials that pursue the sustainable construction, like CEB, the approach of future goals and conditions designed at a national, European and global level is required. The results obtained characterized the CEB as an economically viable and sustainable solution in all the stages of the life cycle, when compared to the remaining kinds of building solutions. After this analysis, it was found that CEB corresponds to these future requirements and it is possible to expect that this kind of material can be increasingly used in the future.
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Soares, Kátia Maria Pereira. "Estudo do comportamento de argamassas de cal em suportes de pedra calcária, tijolos maciços e blocos de terra comprimidos". Master's thesis, 2020. http://hdl.handle.net/10316/98265.
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Dissertação de Mestrado em Reabilitação de Edifícios apresentada à Faculdade de Ciências e TecnologiaEm reabilitação de edifícios antigos, a inevitabilidade de proceder à substituição parcial ou integral dos rebocos quando se encontrem em estado de degradação, determina que esse procedimento deva assumir as características de uma operação de manutenção usual, uma vez que é uma das manifestações patológicas mais comuns.Os novos rebocos aplicados revelam, muitas vezes, reduzida compatibilidade com os suportes, constituindo-se nestes casos como soluções pouco duráveis e potencialmente geradoras de novos processos de degradação das alvenarias.As argamassas de cal são as mais comumente usadas na reabilitação de edifícios antigos por sua capacidade de compatibilização com os suportes, harmonizando-se esteticamente com as alvenarias tradicionais, sendo materiais de alta plasticidade, o que favorece sua conservação.O objetivo deste projeto é desenvolver argamassas de cal (cal área e cal hidráulica), com diferentes tipos de agregados, (areia fina e areia média), na dosagem 1:3, para serem testadas em suportes de blocos de pedra calcária tijolos cerâmicos maciços e blocos de terra comprimidos, sob diferentes processos de cura (cura seca e/ou húmida (28/90 dias)) e cura com “envelhecimento acelerado” de acordo com a norma EN1015-21 e analisar o seu comportamento.O comportamento das argamassas dentro dos moldes laboratoriais não é exatamente o mesmo comportamento das argamassas após aplicação em suporte reais, fato que levou a esta investigação.Assim, criando o cenário mais próximo da realidade de aplicabilidade, ir-se-á investigar o comportamento dos revestimentos de argamassas de cal aérea, cal hidráulica, aplicadas nos suportes já referidos e compará-lo com o comportamento das mesmas argamassas quando endurecidas em moldes laboratoriais.Os ensaios executados e os resultados obtidos serão descritos, apresentados, analisados e comentados.
In rehabilitation of old buildings, the inevitability of partial or complete replacement of mortars when they are in a state of degradation determines that this procedure must has the characteristics of a usual maintenance operation, since it is one of the most common pathological manifestations.The new mortars applied often have reduced compatibility with the substrates, constituting in these cases solutions that are not very durable and potentially generate new masonry degradation processes.Lime mortars are the most commonly used in the rehabilitation of old buildings due to their ability to be compatible with supports, aesthetically harmonizing with traditional masonry, being materials of high plasticity, which favors their conservation.The objective of this project is to develop lime mortars (hydrate lime and hydraulic lime), using different types of aggregates, (fine sand and medium sand), in the 1: 3 dosage, to be applied on limestone, solid bricks and compressed earth blocks. Will be considerate different curing processes (dry and / or wet curing (28/90 days)) and “accelerated aging” curing according to EN1015-21. After de curing process, the lime mortar’s behavior will analyzed.The behavior of mortars when applied within laboratory´s molds is not exactly the same when applied on real substrates. The knowledge about theses different behavior led to this investigation.Thus, creating the scenario closer to the reality of applicability, we will investigate the behavior of hydrate lime mortar and hydraulic lime mortar applied to the aforementioned substrates and compare it with the behavior of the same mortars when hardened in laboratory´s molds.The tests performed and the results obtained will described, presented, analyzed and commented.