To see the other types of publications on this topic, follow the link: Masonry buildings in aggregate.
Dissertations / Theses on the topic 'Masonry buildings in aggregate'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Masonry buildings in aggregate.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Battaglia, Lidia <1991>. "Seismic fragility assessment of unreiforced masonry aggregate buildings." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amsdottorato.unibo.it/9258/1/PhD%20Thesis_Lidia%20Battaglia.pdf.
Full textAbstract:
Aggregate masonry buildings have been generated over the years, allowing the interaction of different aggregated structural units under seismic action. The first part of this work is focused on the seismic vulnerability and fragility assessment of clay brick masonry buildings, sited in Bologna (Italy), with reference, at first, to single isolated structural units, by means of the Response Surface statistical method, taking into account some variabilities and uncertainties involved in the problem. The seismic action was defined by means of a group of selected registered accelerograms, in order to analyse the effect of the variability of the earthquakes. Identical and different structural units chosen by the Response Surface generated simulations are then aggregated in row, in order to compare the collapse PGA referred to the isolated structural unit and the one referred to the aggregate structure. The second part is focused on the seismic vulnerability and fragility assessment of stone masonry structures, sited in Seixal (Portugal), applying a methodology similar to that used for the buildings sited in Bologna. Since the availability of several information, the analyses involved the assessment of the most prevalent structural typologies in the area, considering the variability of a set of structural and geometrical parameters.
The results highlighted the importance of the statistic procedures as method able to consider the variabilities and the uncertainties involved in the problem of the fragility of unreinforced masonry structures, in absence of accurate investigations on the structural typologies, as in the Seixal case study. Furthermore, it was showed that the structural units along the unreinforced clay brick or stone masonry aggregates cannot be analysed as isolated, as they are affected by the effect of the aggregation with adjacent structural units, according to the different directions of the seismic action considered and to their different position along the row aggregate.
2
Boschi, Sonia [Verfasser]. "Seismic risk analysis of masonry buildings in aggregate / Sonia Boschi." Braunschweig : Technische Universität Braunschweig, 2015. http://d-nb.info/1175818739/34.
Full text
3
Bernardini, Chiara Verfasser], Martin [Akademischer Betreuer] [Empelmann, and Andrea [Akademischer Betreuer] Vignoli. "Identification of Minimum Unit of Analysis for seismic performance assessment of masonry buildings in aggregate / Chiara Bernardini ; Martin Empelmann, Andrea Vignoli." Braunschweig : Technische Universität Braunschweig, 2021. http://d-nb.info/1225038235/34.
Full text
4
Bélec, Gilbert. "Seismic Assessment of Unreinforced Masonry Buildings In Canada." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34301.
Full textAbstract:
Unreinforced masonry (URM) structures have shown tobe susceptible to significant
damage during strong earthquakes. Vulnerability assessment of URM buildings is needed so that appropriate mitigation strategies can be implemented. The existing Canadian practice consists of rapid seismic screening of buildings to assign priorities for further and more refined assessments, followed by refined analysis of individual critical buildings. The current seismic screening procedure, from 1992, is based on qualitative observations of seismic vulnerability, enabling the assignment of seismic priority indices, quantified on the basis of expert opinion and experience. More refined tools are needed for seismic vulnerability assessment of URM buildings in Canada, based on the current Canadian
seismic hazard values. The objective of the research project is to fulfill these needs by
developing fragility curves that provide a probabilistic assessment of different levels of
building performance under different intensities ofeastern and western seismicity.
Using an inventory of over 50,000 structures, a seismic assessment of typical low-rise and
mid-rise URM structures located in eastern and western Canada was carried out. The
required analyses were done using applied element method software which effectively
modeled the in-plane and out-of-plane behaviour of masonry walls. Using incremental
dynamic analysis, fragility curves were developed to reflect the capacity of URM
structures with a wide variety of selected structural and ground motion parameters. The
results were verified against available fragility information in the literature. They show the significance of selected parameters, while providing effective tools for seismic
vulnerability assessment of URM buildings in eastern and western Canada.
5
Li, Kai. "Collapse Experiments and Assessment of Masonry Wall Buildings." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1503265342241364.
Full text
6
Valek, Jan. "Lime mortars in historic buildings." Thesis, University of the West of Scotland, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311778.
Full text
7
Marino, Salvatore. "Mechanical behaviour of composite spandrels in unreinforced masonry buildings." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/5951/.
Full textAbstract:
La presente tesi tratta il comportamento meccanico delle fasce di piano in muratura composite. Con tale termine ci si riferisce alle fasce di piano che hanno al di sotto un elemento portante in conglomerato cementizio armato, come ad esempio cordoli o solai. Assieme ai maschi murari, le fasce di piano costituiscono gli elementi portanti di una parete in muratura. Tuttavia, in caso di analisi sismica di un edificio in muratura, l’effetto fornito da tali elementi è trascurato e si considera solamente il contributo dei maschi murari. Ciò è dovuto anche alla scarsa conoscenza che ancora oggi si possiede sul loro comportamento meccanico. Per questo motivo diversi gruppi di ricerca tutt’ora sono impegnati in tale studio. In particolare, il lavoro di questa tesi, s’inserisce nel più ampio progetto di ricerca condotto dalla professoressa Katrin Beyer, direttrice del Laboratorio di Ingegneria Sismica e Dinamica Strutturale del Politecnico di Losanna (Svizzera).
8
Stallbaumer, Cassandra. "Design comparison of hybrid masonry types for seismic lateral force resistance for low-rise buildings." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/32534.
Full textAbstract:
Master of ScienceArchitectural Engineering and Construction Science
Kimberly W. Kramer
The term hybrid masonry describes three variations of a lateral force resisting system that utilizes masonry panels inside steel framing to resist lateral loads from wind or earthquakes. The system originates from the rich history of masonry in the construction industry and is currently used in low-rise, low-seismic, wind-governed locations within the United States. Considerable research is focused on hybrid systems to prove their validity in high-seismic applications. The three variations of hybrid masonry are known by number. Type I hybrid masonry utilizes the masonry panel as a non-load-bearing masonry shear wall. Shear loads from the diaphragm are transferred into the beam, through metal plates, and over an air gap to the top of the masonry panel. The masonry panel transfers the shear to the beam below the panel using compression at the toe of the wall and tension through the reinforcement that is welded to the beam supporting the masonry. Steel framing in this system is designed to resist all gravity loads and effects from the shear wall. Type II hybrid masonry utilizes the masonry as a load-bearing masonry shear wall. The masonry wall, which is constructed from the ground up, supports the floor live loads and dead load of the wall, as well as the lateral seismic load. Shear is transferred from the diaphragm to the steel beam and into the attached masonry panel via shear studs. The masonry panel transfers the seismic load using compression at the toe and opposite corner of the panel. Type III hybrid masonry also utilizes the masonry panel as a load-bearing masonry shear wall, but the load transfer mechanisms are more complicated since the panel is attached to the surrounding steel framing on all four sides of the panel. This study created standard building designs for hybrid systems and a standard moment frame system with masonry infill in order to evaluate the validity of Type I and II hybrid masonry. The hybrid systems were compared to the standard of a moment frame system based on constructability, design, and economics.
9
Wilson, Aaron W. "Seismic assessment of timber floor diaphragms in unreinforced masonry buildings." Thesis, University of Auckland, 2012. http://hdl.handle.net/2292/14696.
Full textAbstract:
An integrated experimental and analytical study investigating the in-plane performance of timber floor diaphragms in URM buildings is presented. The research presented in this thesis was conducted with the primary aim of developing a revised procedure for the detailed seismic assessment of timber floor diaphragms in URM buildings. The deformation mechanics of timber floor diaphragms are presented and were used to develop an analytical model that can be used to predict diaphragm nonlinear performance. The analytical model was used to update the current idealisation of diaphragm behaviour in current seismic assessment documents. A three-phase experimental testing program is presented. Nail connection testing results indicated that connections in diaphragms contained within existing URM buildings have substantially lower initial stiffness, strength, and displacement capacity than do new connections. Small-scale diaphragm testing results proved that friction resistance between straight-edge or tongue and groove floorboards is negligible. Full-scale diaphragm testing results confirmed the highly flexible and orthotropic behaviour of timber floor diaphragms, and that a small stairwell penetration or the presence of discontinuous joists having a reliable mechanical connection do not significantly influence diaphragm performance. A finite element (FE) modelling method for timber floor diaphragms using the structural analysis software SAP2000 was appropriately validated using analytical modelling results and experimental data. Salvaged nail connection load-slip test data was used to program a diaphragm FE model to establish the representative performance of diaphragms in ~100 year old URM buildings in New Zealand. A comprehensive parametric analysis of diaphragm behaviour was subsequently undertaken. Finally, a revised assessment procedure for timber floor diaphragms was developed, which incorporates representative performance parameters, and provides suitable provisions to account for diaphragm orthotropic behaviour and for variations in key diaphragm configuration characteristics.
10
Lumantarna, Ronald. "Material Characterisation of New Zealand's Clay Brick Unreinforced Masonry Buildings." Thesis, University of Auckland, 2012. http://hdl.handle.net/2292/18879.
Full textAbstract:
This thesis reports the investigation on the material properties of New Zealand's heritage clay brick unreinforced masonry (URM) buildings. The primary focus of this doctoral investigation was to establish a methodology to determine the material properties of existing New Zealand URM buildings. Although researchers from Europe, USA, India and Australia have previously studied the material properties of clay brick unreinforced masonry, knowledge on New Zealand URM material properties was poor at the time the study commenced. Therefore, a research programme that primarily focused on the testing of samples extracted from existing New Zealand URM buildings was undertaken. Vintage clay bricks and irregular mortar samples were extracted from existing New Zealand URM buildings, and were subjected to a series of non-destructive tests before being tested in compression. The relationships between the non-destructive test results and the clay brick and mortar compressive strengths were studied, and non-destructive testing techniques that were most suitable for estimating clay brick and mortar compressive strengths in-situ were proposed. Also, a methodology for the compression testing of irregular mortar samples that are extracted from existing URM buildings and a technique to normalise the irregular mortar compression test results were developed. The compressive strength and compressive stiffness of masonry were studied using masonry prisms that were both extracted from existing buildings and were constructed in the laboratory. Empirical relationships relating the brick unit, mortar and masonry compressive strengths as well as relating the masonry compressive strength to the masonry Modulus of Elasticity were derived. Also, numerical models for the compression stress-strain relationship of masonry were proposed. The flexural bond strength and shear bond strength of masonry were studied using field extracted and laboratory constructed masonry prisms. Empirical relationships relating the mortar compressive strength to the flexural bond strength and to the bed joint cohesion were derived. Finally, a procedure to assess the material properties of existing New Zealand URM buildings was recommended.
11
Yaseen, Abdulhameed Abdullah. "Seismic fragility assessment of masonry buildings in the Kurdistan region." Thesis, University of Portsmouth, 2015. https://researchportal.port.ac.uk/portal/en/theses/seismic-fragility-assessment-of-masonry-buildings-in-the-kurdistan-region(68d3f8fb-c760-4a1c-a10f-86f103686f9f).html.
Full textAbstract:
The collapse of building structures during recent earthquakes, particularly in the countries around the Kurdistan region (KR), including Turkey (2011 Van earthquake) and Iran (2003 Bam earthquake), has raised many questions about the safety of existing buildings in the region and structures that are going to be constructed in the future. The KR, which is located in northern and northeastern Iraq, is also considered to be the most hazardous region of Iraq. However, many buildings in the region, especially unreinforced masonry (URM) buildings, were not engineered to withstand seismic loads. The seismic vulnerability assessment of these types of buildings in this region is a necessary step towards the development of regional seismic retrofitting and pre-disaster mitigation plans. Fragility analysis is often used for this purpose and to graphically represent a structure’s seismic vulnerability in terms of fragility curves. Considering that there are several important uncertainties involved in such an analysis and after developing and proposing seismic zonation maps, response spectra and the seismic zone factor Z for the KR, the results of analytical fragility analyses of URM buildings in the KR indicated that the correct selection of a ground-motion intensity measure (IM) is the most important variability involved in assessing the fragility of URM buildings. The results suggest that the variability in the mechanical parameters of materials can be neglected because the variability of ground motion is considerably more substantial. Furthermore, the use of incremental dynamic analysis (IDA) and a well-selected IM allows fragility curves to be derived with only a few records (i.e., a minimum of 7 records) with the same performance as for with numerous records (i.e., 60 records). Moreover, the pronounced difference in the results when using only one IM vs. using two IMs cannot be ignored; hence, fragility surfaces are preferred over the more commonly used fragility curves. Furthermore, a framework based on using machine learning models (i.e., a wrapper-based approach) for the optimal selection of an IM for developing fragility curves is proposed in this study. The feasibility of the wrapper method for selecting the best IM is compared to a statistical regression (log-logistic regression) used to develop fragility curves and the results were encouraging. Finally, the outcomes of the study indicate that the seismic safety of the investigated low-rise buildings in the region is questionable and that these structures must be strengthened to prevent failure.
12
Liu, Gang. "Numerical modelling of damage to masonry buildings due to tunnelling." Thesis, University of Oxford, 1997. http://ora.ox.ac.uk/objects/uuid:c1390020-daba-40cc-b922-e27314bea2b5.
Full textAbstract:
Accurate assessment of the damage to buildings due to tunnelling in soft ground becomes an important issue when a tunnel is constructed under historic masonry buildings in urban areas. The current two-stage approach in which settlements estimated from a Gaussian curve are applied to a building does not consider soil-structure interaction and fails to give a correct prediction of the damage. This thesis describes a complete threedimensional finite element model for assessment of the settlement damage to masonry buildings induced by tunnelling in London Clay, and an investigation of the interaction between a masonry building and the ground. A macroscopic elastic no tension model, which assumes the material has zero tensile strength but infinite compressive strength, is developed to simulate the behaviour of masonry. Numerical techniques are proposed to improve the stability of the calculation. The comparison of the no tension and elastic models, by applying Gaussian curve settlement troughs to both a plain wall and a facade, shows that the no tension model predicts different behaviour of the masonry building during tunnelling, including different cracking patterns and damage grades. Two-dimensional finite element analyses combining the building, modelled by the no tension material, and the ground, modelled by a nested yield surface model, give insight into the interaction between the masonry structure and the ground. They suggest the importance of the stresses in the soil prior to the excavation in affecting the ground movements during tunnelling. Thus the weight of the building controls the overall magnitude of the ground movements beneath the building, while the stiffness of the building affects the shape of the trough. A key aspect of the behaviour of the masonry building is the formation of stress arches. Finally the three-dimensional finite element analyses are described. Both symmetric and unsymmetric cases are analysed. The results show that the three-dimensional analysis gives more realistic modelling of the problem and is likely to be necessary for practical situations, especially when a building is not symmetrically located with respect to the tunnel - a case which cannot be analysed in two-dimensions. A special tying scheme is proposed for the connection of the nodes belonging to elements of different types, which are defined in their own local co-ordinate systems. Different types of tie elements are formulated and implemented for connection between two-dimensional and three-dimensional elements in various combinations.
13
Buntrock, Rebecca (Rebecca Miriam). "Structural performance of early 20th century masonry high rise buildings." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/60760.
Full textAbstract:
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 65-67).
Early generation high rise buildings built between 1890 and World War 11 represent a technical transition between traditional load bearing masonry construction and modern curtain wall systems, and are typically referred to as 'transitional masonry buildings'. These structures comprise a large percentage of the building stock constructed in the early twentieth century. Two pertinent issues have emerged with these structures as they age. The first is the deterioration of the exterior masonry facade, which is largely a result of deficiencies in the construction method of these structures. The second issue is that it is very difficult to properly predict their structural performance because of the complicated interaction between the masonry infill and the structural frame. Underestimating or misdiagnosing the structural performance of a transitional masonry building can result in improper interventions. The aim of this thesis is to increase the understanding of the structural and facade performance of transitional masonry buildings and present methods for their analysis. A case study of a transitional masonry building is structurally analyzed using linear and nonlinear procedures to determine the contribution of the masonry infill as well as to investigate the feasibility of using simplified analytical models to predict structural performance.
by Rebecca Buntrock.
M.Eng.
14
Whiting, Emily Jing Wei. "Design of structurally-sound masonry buildings using 3D static analysis." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/70102.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 95-100).
In the design of buildings, structural analysis is traditionally performed after the aesthetic design has been determined and has little in uence on the overall form. This thesis presents methods to integrate architectural design and structural analysis. While existing tools focus on providing an analysis of the stress state, the proposed methods focus on geometry and equilibrium to obtain forms that are more structurally sound. The feasibility of masonry structures is modeled using a novel penalty formulation, assuming a rigid-block behavior of masonry. Two methods were developed that apply this model of feasibility to structural optimization. In the first approach, structural feasibility is introduced into procedural modeling of buildings. A set of designated free parameters are automatically tuned to achieve structural feasibility constraints. It is demonstrated how this allows for more realistic structural models that can be interacted with in physical simulations. In the second approach, a closed form derivation of structural gradients is presented that measures the change in stability of a building with respect to geometry modifications. The method computes the gradient of structural feasibility constraints, parameterized by vertex modifications. The gradients are visualized as interaction tools, giving user-guidance for effectively modifying a structural design. User-controlled constraints, formulated as penalty functions, are incorporated so that the user can explore variations of structurally feasible designs.
by Emily Jing Wei Whiting.
Ph.D.
15
Sicha, Pillaca Juan Carlos, Ramirez Alexander Molina, and Victor Arana Vasquez. "Structural design of confined masonry buildings using artificial neural networks." Institute of Electrical and Electronics Engineers Inc, 2020. http://hdl.handle.net/10757/656414.
Full textAbstract:
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.The aim of this article is to use artificial neural networks (ANN) to perform the structural design of confined masonry buildings. ANN is easy to operate and allows to reduce the time and cost of seismic designs. To generate the artificial neural network, training models (traditional confined masonry designs) are used to identify the input and output parameters. From this, the final architecture and activation functions are defined for each layer of the ANN. Finally, ANN training is carried out using the backpropagation algorithm to obtain the matrix of weights and thresholds that allow the network to operate and provide preliminary structural designs with a 10% margin of error, with respect to the traditional design, in the dimensions and reinforcements of the structural elements.
16
Capanna, Ilaria. "Simplified multicriteria method for seismic assessment of unreinforced masonry buildings." Doctoral thesis, Università degli Studi dell'Aquila, 2022. https://hdl.handle.net/11697/198067.
Full textAbstract:
The aims and motivations that were driven this PhD thesis arise from the common interest on the mitigation of the seismic risk, wide field of continuous relevance and of interest for different disciplines. The scientific community, specially in engineering field, reserves attentions on the mitigation of the seismic risk. The human and economic losses, caused by fragilities of the urban centres, manifested in the aftermath of a seismic event, confirm the need of research effort. The PhD thesis presents a multi criteria method for seismic assessment of unreinforced masonry buildings, URMs. The majority of the built environment consists of URMs. The study of their seismic behaviour is exasperated by the ageing of materials, the lack of anti-seismic criteria, construction process, architectural alterations or restorations, and the poor mechanical properties of used materials. Nevertheless, URMs are unique constructions for their historical and architectural value, that need to be protected against earthquakes. The knowledge of structural fragilities of urban centres is a prerequisite to face the mitigation of the seismic risk. Simplified assessment methods arise to overcome the effort and time consuming of analysis at a large scale of the built environment, by means the introduction of several simplifications.
The proposed multi criteria vulnerability method provides a quick assessment based on few structural parameters, known from field observations and geometric survey, to overcome excessive computational demand, thanks to two different levels of evaluation. The first level of the vulnerability assessment method bases on the evaluation of few structural parameters to perform a first screening of the seismic fragilities. The second level predicts the seismic capacity of masonry walls more accurately respect to the empirical one, to establish strengthening measures or strategies more accurately. Therefore, the multi criteria method could support the activities of authorities and stakeholders in the mitigation of the seismic risk of the built environment. The thesis consists of eight chapters. The first chapter introduces an overview on the seismic risk, as field of the research activity. The second chapter concerns the state of the art of structural vulnerability, the structural vulnerability. An in-depth classification of seismic vulnerability assessment methods is reported. The third chapter regards the test-site of the research activity. The fourth chapter reports the dynamic campaign on a URM, chosen as representative of the structural class. The aim of this activity was to investigate the influence of a suite of structural parameters influencing the building behaviour. The fifth chapter introduces the first level of the predictive multi-criteria method. The empirical method aims to estimate the seismic vulnerability through the evaluation of a few structural parameters, ensuring a quick application. The derivation and validation of the formulations' method are reported. The last part of the chapter compares the method with others available from the literature, to highlight its reliability and advantages. The sixth chapter illustrates possible applications of the empirical predictive method. The seventh chapter discusses the second level of the proposed method. It aims to grasp the seismic vulnerability of buildings, with a higher accuracy than the first level. The eighth chapter completes the PhD thesis, with a broader point of view, to explain the results and future developments.
17
De, Viti Caterina. "Historic Adobe Masonry Buildings in Portugal: Material Characterization and Numerical Modelling." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
Find full textAbstract:
Nel corso degli ultimi decenni, le costruzioni in terra cruda sono tornate al centro del dibattito tra architetti e ingegneri di tutto il mondo, non solo perché costituiscono una vasta porzione del patrimonio architettonico mondiale, ma anche perché rappresentano una valida alternativa nell’ambito della sostenibilità alle tradizionali tipologie costruttive.
In Portogallo, fino alla metà del XX secolo, ebbero molta diffusione gli edifici realizzati in adobe, ovvero in muratura di mattoni in terra cruda. Ad oggi, molte di queste architetture, di cui alcune in stile Art Noveau di grande valore storico e artistico, si trovano in pessimo stato di conservazione.
Risulta quindi fondamentale promuovere programmi di ricerca multidisciplinari finalizzati a fornire validi strumenti per il recupero e il rinforzo strutturale di questi edifici.
In questo contesto, il presente studio ha come obiettivo quello di implementare la conoscenza delle proprietà della muratura in adobe e in particolare dei parametri di resistenza meccanica.
A questo scopo, ho condotto test sperimentali su mattoni provenienti dalla città portoghese di Aveiro per meglio caratterizzare le proprietà e la natura del materiale. Nello specifico, ho analizzato campioni cubici di adobe tramite prova di assorbimento d’acqua, analisi della distribuzione granulometrica, calcimetria e diffrattometria a raggi X. Sono stati poi effettuati test di compressione assiale su dodici provini cubici di adobe con diversi tenori di umidità per verificare in che modo e in che misura la presenza di umidità influenzi il comportamento meccanico e la resistenza di questo materiale.
Ho inoltre realizzato la calibrazione di un programma di modellazione numerica (Nastra In-Cad) e, nella parte finale della ricerca, lo stesso programma è stato utilizzato per prevedere il comportamento di porzioni murarie in adobe con diversi tenori di umidità, utilizzando i valori ottenuti dai test di compressione sperimentali.
18
Ismail, Najif. "Selected strengthening techniques for the seismic retrofit of unreinforced masonry buildings." Thesis, University of Auckland, 2012. http://hdl.handle.net/2292/19106.
Full textAbstract:
Approximately two thirds of the fatalities caused by earthquakes in the last one hundred years have resulted due to the collapse of unreinforced masonry (URM) buildings. Poor performance of URM buildings was also observed in recent earthquakes such as the 2005 Pakistan earthquake, the 2008 Sichuan earthquake, the 2009 L'Aquila earthquake and the 2010/2011 Canterbury (New Zealand) earthquake sequence. The New Zealand URM building stock consists of mostly pre-1931 structures, with many of these buildings contributing to the country's architectural heritage. It was revealed in a recent survey that many of New Zealand's URM buildings have insufficient capacity to endure even a moderate earthquake but the concerns of heritage preservation makes demolition of these historic URM buildings undesirable, which results in seismic retrofit being necessary. Many seismic retrofit solutions have already been implemented in New Zealand, but the experimental database on their seismic behaviour is scarce. Consequently, the research reported here was undertaken to investigate the performance of URM walls when seismically retrofitted using three strengthening techniques, which were selected after an extensive literature review. The selected strengthening techniques are (i) unbonded posttensioning using threaded steel rods and sheathed greased strands, (ii) near surface mounting of high strength twisted stainless steel bars (NSM-TS), and (iii) surface application of polymer textile reinforced mortar (TRM). The selected seismic strengthening techniques were adapted for New Zealand URM buildings, and the performance of URM walls seismically strengthened using the adapted strengthening techniques was investigated by performing numerous full scale laboratory based and field tests. Based on the results of the experimental program empirical design equations were derived and checked for accuracy by comparing with current design equations and with experimental results. Finally, case studies were conducted to demonstrate application of these strengthening techniques for the seismic retrofit of historic URM buildings.
19
Ozturk, Mehmet Selim. "Effects Of Masonry Infill Walls On The Seismic Performance Of Buildings." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606753/index.pdf.
Full textAbstract:
In Turkey, in most of the reinforced concrete buildings, hallow masonry infill walls are used as a non-structural element, during design stage, their contribution to overall building behavior is not well known. Observations made after the earthquakes revealed that these non-structural elements had beneficial effects on the lateral capacity of the building.
In this study, the contribution of the hallow masonry infill walls to the lateral behavior of reinforced concrete buildings was investigated. For this purpose, two different buildings were chosen as case studies. Three and six story symmetric buildings are modeled as bare and infilled frames. The parameters that were investigated are column area, infill wall area, distribution of masonry infill walls throughout the story. To determine the effect of each parameter, global drift ratios are computed and are compared for each case.
20
Ali, Jabbar Talib. "Structural design and analysis of masonry buildings using thin joint mortar." Thesis, University of Surrey, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540708.
Full text
21
Spencer, Emily D. (Emily Deen). "Seismic assessment of unreinforced masonry buildings in Boston's Back Bay neighborhood." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/99634.
Full textAbstract:
Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 70-72).
This thesis presents a seismic evaluation of the unreinforced masonry buildings in Boston Massachusetts's historical Back Bay neighborhood. This Boston district, famous for its rows of Victorian brownstone residences is considered to be one of the best preserved examples of 19 'h century urban design. There are a few specific reasons to speculate at the vulnerability of this neighborhood to seismic events. First, in 1755, one hundred years before the Back Bay started to be built, the most massive earthquake of New England's history occurred, damaging unreinforced masonry structures in Boston. Approximately eighty percent of the Back Bay neighborhood is now made up of unreinforced masonry structures. Second, seismic design was not required in Boston until 1975, which means a staggering majority of the buildings in the Back Bay were constructed without any kind of anti-seismic lateral system. The aim of this thesis is to assess the structural response of the unreinforced masonry homes of the Back Bay to seismic activity due to these issues. A case study of an unreinforced masonry building in the neighborhood is assessed through structural analysis of its facade and party walls. The performance of this building is extrapolated to represent the state of the unreinforced masonry buildings of the Back Bay.
by Emily D. Spencer.
M. Eng.
22
Kayan, Brit Anak. "Green maintenance for historic masonry buildings : a life cycle assessment approach." Thesis, Heriot-Watt University, 2013. http://hdl.handle.net/10399/2676.
Full textAbstract:
This research establishes the concept of ‘Green Maintenance’ modelling for historic masonry buildings. It recognises the important role of maintenance and repair in reducing embodied carbon expenditure, thus minimising the Environmental Maintenance Impact (EMI) typically associated with the deterioration of external stone masonry walls. The model was developed using a mathematical framework, and it generated results described in terms of EMI. This model utilises life-cycle assessment (LCA) ‘cradle-to-site’ over a selected maintenance period. The work evaluates embodied carbon expenditure from different stone masonry wall repair techniques for historic masonry buildings during their maintenance phase. It was discovered that embodied carbon expenditure for these repair techniques are highly influenced by the number of maintenance interventions, longevity of repairs, total wall surface repaired (m2), the embodied carbon coefficient value (‘cradle-to-gate’) and kg/km emission factors (‘gate-to-site’) associated with materials and repair processes. Based on the EMI in terms of embodied carbon expenditure generated from the results of ‘Green Maintenance’, the efficiency of stone masonry wall repair techniques can be determined. This not only aids in maintenance decisions making processes, but also contributes in substantiating the philosophical defensibility and sustainability of interventions. In the broader sense, this model is not simply confined to masonry and will be of use to those entrusted with the repair of other elements and components.
23
Silveira, Dora Susana Gomes da. "Constructive and mechanical characterisation of adobe masonry walls of existing buildings." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17313.
Full textAbstract:
Doutoramento em Engenharia CivilEarthen construction has been widely used throughout the world, since approximately 10000 years ago and until the present day. A significant part of the world earthen built heritage – including many properties inscribed on the UNESCO’s World Heritage List –, however, is at risk. In Portugal, earth was also a widely used construction material until the middle of the 20th century. In Aveiro district, in particular, adobe construction was very common. Currently, there are still a great number of adobe constructions in this region, a large part of which are in use. Many of the existing buildings are of social, cultural, and architectural value. Despite their value, however, many of these buildings are in a poor state of conservation, suffering from various structural and non-structural defects. The problems observed in existing adobe buildings result in large part from a lack of knowledge regarding the materials and building systems used in this type of construction. There is, in particular, a lack of knowledge about the properties and behaviour of adobe masonry walls, which are key structural elements that influence the overall behaviour of buildings. The main aim of the research developed and discussed in this thesis is thus to contribute to this knowledge, focusing, in particular, on the adobe buildings of Aveiro district. For this purpose, a visual and dimensional inspection of the facade walls of twenty-one representative adobe buildings was conducted. With this inspection, it was possible to carry out a detailed analysis of the facade walls – including their structural system, coatings, and traditional masonry materials – and to assess the vulnerabilities, common defects, and state of conservation of these elements. A series of experimental tests were also carried out. Simple compression tests were performed on cylindrical and cubic adobe specimens, flexural tests on adobe bricks, and splitting tests on cylindrical specimens. Simple compression and diagonal compression tests were also conducted on ten full-scale adobe masonry wall panels, built with adobes taken from an existing construction. Finally, an in-plane horizontal cyclic test was performed on a full-scale double-T shaped adobe wall, also built with adobes from an existing construction. With the tests carried out, it was possible to characterise the strength, stiffness, stress-strain relationships, and common damage pattern of the test specimens, and to assess correlations between different mechanical properties. It was also possible to develop a comparison between the strength values obtained and the limits indicated in existing standards for earthen construction, and between the results obtained and those determined by other authors for test specimens representative of adobe construction in other countries. The results presented and discussed in this thesis contribute to the enrichment of knowledge that is considered essential to support the conservation and rehabilitation of existing adobe buildings, not only in Portugal, but also in other regions of the world.
A construção em terra tem sido muito utilizada em todo o mundo, desde há cerca de 10000 anos atrás e até aos dias de hoje. Uma parte significativa do património mundial construído com terra, incluindo vários bens inscritos na Lista de Património Mundial da UNESCO, encontra-se, no entanto, em risco. Em Portugal, a terra foi também um material de construção muito utilizado até meados do século XX. No distrito de Aveiro, em particular, a construção em adobe era muito comum. Atualmente, existe ainda um elevado número de construções em adobe nesta região, grande parte das quais se encontram em uso. Muitos dos edifícios existentes são de valor social, cultural e arquitetónico reconhecido. No entanto, apesar do seu valor, muitos destes edifícios estão em mau estado de conservação, apresentando anomalias estruturais e não estruturais variadas. Os problemas observados nos edifícios existentes de adobe resultam, em grande parte, de falta de conhecimento sobre os materiais e sistemas de construção utilizados neste tipo de edificação. Há, em particular, falta de conhecimento sobre as propriedades e o comportamento das paredes de alvenaria de adobe, que são elementos estruturais principais que influenciam o comportamento global dos edifícios. Assim, o trabalho de investigação desenvolvido e discutido nesta tese tem como principal objetivo contribuir para este conhecimento, debruçando-se, em particular, sobre as construções em adobe do distrito de Aveiro. Para este efeito, foi realizada uma inspeção visual e dimensional das paredes de fachada de vinte e um edifícios de adobe representativos. Com esta inspeção, foi possível analisar de forma detalhada as paredes de fachada – incluindo o seu sistema estrutural, revestimentos e materiais de alvenaria tradicionais – e avaliar as vulnerabilidades, anomalias comuns e estado de conservação destes elementos. Uma série de ensaios experimentais foi também levada a cabo. Foram realizados ensaios de compressão simples sobre provetes cilíndricos e cúbicos de adobe, ensaios de flexão sobre blocos de adobe e ensaios de compressão diametral sobre provetes cilíndricos. Foram ainda realizados ensaios de compressão simples e compressão diagonal sobre dez painéis de alvenaria de adobe à escala real, construídos com adobes recolhidos de uma construção existente. Por fim, realizou-se o ensaio de uma parede à escala real em forma de ‘duplo T’, construída também com adobes de uma construção existente, sob a ação de uma carga horizontal cíclica, aplicada no plano da parede. Com os ensaios realizados, foi possível caracterizar a resistência, a rigidez, as relações de comportamento tensão-deformação e o padrão comum de dano dos elementos ensaiados, e avaliar as correlações entre diferentes propriedades mecânicas. Foi ainda desenvolvida uma comparação entre os valores de resistência obtidos e os limites indicados nas normas existentes para a construção em terra, bem como entre os resultados obtidos e aqueles determinados por outros autores para a alvenaria de adobe representativa da construção em adobe noutros países. Os resultados apresentados e discutidos nesta tese contribuem para o enriquecimento de conhecimento que é considerado essencial para apoiar a conservação e reabilitação dos edifícios de adobe existentes, não só em Portugal, mas também noutras regiões do mundo.
24
Korany, Yasser Drysdale Robert G. "Rehabilitation of masonry walls using unobtrusive FRP techniques for enhanced out-of-plane seismic resistance /." *McMaster only, 2004.
Find full text
25
Halsey, David Piers. "The weathering of sandstone, with particular reference to buildings in the West Midlands, UK." Thesis, University of Wolverhampton, 1996. http://hdl.handle.net/2436/90754.
Full text
26
Abdul, Karim Abdul Razak. "Seismic assessment of wall-diaphragm connections in New Zealand unreinforced masonry buildings." Thesis, University of Auckland, 2012. http://hdl.handle.net/2292/19238.
Full textAbstract:
This study presents the seismic assessment of wall-diaphragm connections in New Zealand unreinforced masonry buildings, particularly on the bolted connections applied to the existing timber members of the floor and roof diaphragms. Because of the lack of data on the local indigenous hardwood bolted connections, the experimental study to assess their strength performance was initiated. Materials tested were recycled Matai and Rimu hardwoods, which are typically used in the construction of diaphragms in New Zealand unreinforced masonry buildings. The basic properties of the timber used were determined by conducting the following tests: (1) moisture content and density tests; (2) embedding strength tests parallel to the timber grain; and (3) yield compression strength tests perpendicular to the timber grain. The main timber bolted connection tests were conducted in accordance with the ISO/DIS 10984-2. Eleven groups of different bolted connection details with at least ten replicates for each group were tested. A steel-wood-steel connection type was applied to all tested specimens. Based on the current design equations of New Zealand code, European Yield Model, and Row Shear Model, the strength prediction values were compared with the test results obtained. From the comparison made, the effectiveness of those equations to predict the bolted connection strength was identified. The use of European Yield Model and Row Shear Model equations to assess the bolted connection strength in New Zealand hardwoods is recommended. A procedure that was particularly developed to assess the wall diaphragm connections in New Zealand unreinforced masonry buildings is also presented in this thesis.
27
Dymiotis, Christiana. "Probabilistic seismic assessment of reinforced concrete buildings with and without masonry infills." Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/8666.
Full text
28
Sickels, L. B. "Mortars in old buildings and masonry conservation : A historical and practical treatise." Thesis, University of Edinburgh, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379336.
Full text
29
Loots, Jurie. "Computational assessment of seismic resistance of RC framed buildings with masonry infill." Thesis, Stellenbosch : Stellenbosch University, 2005. http://hdl.handle.net/10019.1/50299.
Full textAbstract:
Thesis (MScIng)--Stellenbosch University, 2005.Some digitised pages may appear illegible due to the condition of the original hard copy.
ENGLISH ABSTRACT: Reinforced concrete (RC) frames with unreinforced masonry infill form the structural system of many buildings and this is also true for South Africa. It is common practice to consider the masonry infill as a non-structural component and therefore it does not contribute to the performance of the Re frame buildings under lateral loading such as earthquake loading. This is done by leaving a sufficient gap between the Re frame and the infill. This ensures that there is no contact between the frame and the infill during an earthquake event. However, it has been suggested that masonry infill can play a significant role in the performance of a Re frame building under lateral loading. The first part of the study focuses on the South African situation. The relevance of shear walls in these Re frame buildings as well as the size of the gap (between frame and infill) left in practice, are investigated. This is done by finite element analysis. The second part of the study focuses on the effects that the infill can have on the global performance of the structure when there is full contact between the Re frames and infill. The effect of openings in the infill to the response of the frame is also investigated. Finite element models of single span Re frames with infill is built and analyzed in order to investigate possible damage to the infill, frame infill interaction and to obtain the non linear stiffness of the frame with infill as a whole. This obtained non linear stiffness can be modelled in Diana as a non linear spring that will be used in the development of a simplified analysis method. The simplified method developed consists of a frame and two such non linear springs, placed diagonally, and which have the same force versus displacement behaviour as the original frame with infill. These single span frames can be added together to model a whole frame. In a first step to generalise the simplified method, various geometries of infills are considered, varying span and height, as well as opening percentage, representing windows and doors of varying total area and positioning. However, in this study a single masonry type, namely solid baked clay bricks set in a general mortar, is considered. To generalise the approach further, other masonry types can be considered in the same way. The use of these springs in a simplified model saves computational time and this means that larger structures can be modelled in Diana to investigate response of'Rf' frame buildings with infill. The work reported in this thesis considers only in-plane action. Out-of-plane-action of the masonry infill has been reported in the literature to be considerable, under the condition that it is sufficiently tied to the frame to prevent mere toppling over, causing life risking hazards in earthquake events. This matter should be studied in continuation of the current research to generalise the simple approach to three dimensions.
AFRIKAANSE OPSOMMING: Gewapende betonrame (GBR-e) met ongewapende messelwerk invulpanele (invul) vorm die strukturele ruggraat van vele geboue en dit geld ook vir geboue in Suid-Afrika. Dit is algemene praktyk om die invulpaneel in sulke geboue as 'n nie-strukturele komponent te beskou. Daarvolgens dra dit nie by tot die gedrag van 'n GBR gebou onderhewig aan 'n aarbewing nie. Dit word bereik deur 'n groot genoeg gaping tussen die betonraam en die invul te los. Die gevolg is dat daar geen kontak tussen die betonraam en die invul plaasvind indien daar 'n aardbewing sou voorkom nie. Dit is egter voorgestel dat invul 'n noemenswaardige rol kan speel in die gedrag van 'n GBR gebou onderwerp aan 'n horisontale las. Die eerste deel van die studie fokus op die Suid-Afrikaanse situasie. Die relavansie van skuifmure in GBR geboue asook die grootte van die gaping (tussen die raam en invul) wat in die praktyk gebruik word, word ondersoek. Dit word gedoen met behulp van eindige element analises. Die tweede deel van die studie fokus op die effek wat invul kan hê op die globale gedrag van 'n struktuur wanneer daar volle kontak tussen die GBR en die invul is. Die effek wat die teenwoordigheid van openinge in die invul kan hê op die gedrag van 'n GBR is ook ondersoek. Eindige element modelle van enkelspan GBR met invul is gemodelleer en geanaliseer om die moontlike skade aan die invul, die interaksie tussen die GBR en die invul asook die nie-lineêre styfheid van die raam en invul as 'n geheel, te ondersoek. Hierdie nielineêre styfheid kan in Diana as 'n nie-lineêre veer gemodelleer word en word gebruik in die ontwikkeling van 'n vereenvoudigde metode. Hierdie vereenvoudigde metode wat ontwikkel is, bestaan uit 'n raam en twee sulke nielineêre vere (diagonaal geplaas). Die raam met vere het dieselfde krag teenoor verplasingsgedrag as die van die oorspronklike raam met invul wat dit voorstel. Hierdie rame kan saamgevoeg word om 'n raam uit 'n gebou as 'n geheel te modelleer. Verskeie invul geometrieë word gebruik in die analises in 'n eerste stap om die vereenvoudigde metode te veralgemeen. Die span en hoogte asook opening persentasie van die invul word gevariëer om vensters en deure van veskeie grootte en posisie voor te stel. In die studie, 'n enkel messelwerk tipe, naamlik solied klei bakstene geset in algemene mortar, word gebruik. Ander messelwerk tipes kan gebruik word om die metode verder te veralgemeen. Die gebruik van die vere in die vereenvoudigde metode spaar berekenings tyd en dit beteken dat groter strukture in Diana gemodelleer kan word om die gedrag van GBR geboue met invul te ondersoek. Die werk gedoen in die tesis neem slegs in-vlak aksie in ag. Literatuurstudie dui daarop dat goeie uit-vlak-aksie van messelwerk invul bestaan, mits dit goed geanker is aan die raam om te verseker dat dit nie kan omval en 'n gevaar vir lewens in 'n aardbewing inhou nie. Dit behoort verder bestudeer te vord in die vervolging van die huidige ondersoek om die vereenvoudige metode na drie dimensies te veralgemeen.
30
Naeem, Qazi Sulaiman. "Finite element modelling and response spectrum snalysis of Rubble-Stone Masonry Buildings." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23767/.
Full textAbstract:
Finite element modelling is an efficient tool for the performance assessment of masonry structures. In particular, it facilitates the accurate prediction of the seismic response of a structure to earthquakes using dynamic analysis procedures. Numerical models using response spectrum analysis based on modal analysis allow to predict realistic failure modes observed after preceding seismic events with reasonable computational effort, a characteristic which is suitable for engineering practice. This thesis deals with modelling as a finite element model and analyse using response spectrum analysis of masonry buildings and the subsequent discussion of the obtained results. SAP2000 software is used for developing the numerical models, which are then analysed on the basis of design acceleration response spectra obtained according to the different building codes for different regions. Different structural demands under static and dynamic loading are obtained from the models and compared with theoretical results made with various mathematical models.
31
Ibrahim, Khaled S. (Khaled Sayed) Carleton University Dissertation Engineering Civil. "Thermal stresses in lowrise loadbearing concrete masonry buildings: a finite element study." Ottawa, 1989.
Find full text
32
Mazzon, Nicola. "Infuence of Grout Injection on the Dynamic Behaviour of Stone Masonry Buildings." Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3422728.
Full textAbstract:
The Italian and European regions are characterized by a wide diffusion of structures in the minor historical centres. The decay condition, in which part these buildings are, makes often necessary structural interventions to preserve they integrity. This way, during last decades several new intervention methodologies were developed, employing both innovative and traditional materials, with the aim to avoid further damages, particularly those induced by seismic events. However, these new materials and techniques are often commercialized and employed without any preliminary exhaustive study to verify their applicability and their effectiveness.
The present research joins in this contest considering the multi-leaf stone masonries, one of the most diffuse structural systems widely employed on minor historical buildings. This masonry typology is constituted by more approached leaves and it is characterized by a high percentage of internal voids. Furthermore, the employment of hydraulic lime-based grout injection is also considered as strengthening technique suitable for this masonry typology. This study aims to validate the application of this intervention methodology, widely applied since many years employing materials different for chemical composition, trough an extensive experimental campaign and a subsequent numerical modelling.
First experimental phase involves a series of dynamic tests on whole building models, considering a reducing scale factor, realized with multi-leaf stone masonry, subsequently strengthened trough injection of grout. The execution of these shaking table tests allowed to evaluate the influence of the considered strengthening technique on the overall dynamic behaviour of the injected structure. Furthermore, also the increasing of strength and the seismic response of the building models could be evaluated.
A complementary experimental phase involved several further quasi-static laboratory tests tests on single structural elements.
Compression tests allowed to study the strength increasing of this elements as well as their failure mechanisms after the grout injection. Further shear compression tests provided important informations about the mechanical behaviour of single structural elements subjected to in-plane cyclic forces.
Finally, a numerical modelling of the mechanical behaviour of specimens subjected to compression load was developed. This analysis allowed to deepen the study of the stress distribution and of the failure mechanisms of single structural elements subjected to strengthening trough grout injection.Il territorio italiano, così come quello europeo, è caratterizzato da un’ampia diffusione di strutture appartenenti all’edilizia storica minore. Lo stato di degrado, in cui talvolta si trovano tali edifici, rende spesso necessari interventi strutturali volti a garantirne l’integrità. In tale senso, negli ultimi decenni sono state sviluppate nuove metodologie d’intervento, sfruttando sia di materiali tradizionali che innovativi, per preservare tali strutture da ulteriori danni, in particolare quelli indotti da eventi sismici. Tuttavia, nuovi materiali e tecniche d’intervento vengono spesso commercializzati ed applicati senza l’esecuzione di un esaustivo studio preliminare che ne verifichi l’applicabilità e l’efficacia. La presente ricerca si inserisce in questo contesto prendendo in considerazione le murature multi-strato in pietra, una delle tipologie costruttive maggiormente impiegate nell’edilizia storica minore. Tale muratura è costituita da più paramenti accostati ed è caratterizzata da un’alta percentuale di vuoti interni. Inoltre, si considera l’impiego dell’iniezione di miscela, a base di calce idraulica naturale, come tecnica di consolidamento applicabile a tale tipologia muraria. Lo studio si propone di validare l’impiego di questa metodologia d’intervento, già da tempo ampiamente utilizzata sfruttando materiali di diversa composizione chimica, mediante la realizzazione di un’ampia campagna sperimentale e di una successiva modellazione numerica. La prima fase sperimentale comprende una serie di prove dinamiche su modelli di edificio, in scala ridotta, realizzati in muratura multi-strato di pietra, successivamente sottoposta ad iniezione di miscela. L’esecuzione di tali prove su tavola vibrante ha permesso di valutare l’influenza della tecnica di consolidamento considerata sul comportamento dinamico globale della struttura su cui si interviene. Inoltre, si è potuto valutare l’incremento di resistenza oltre che la variazione della risposta sismica dei modelli di edificio. Una complementare fase sperimentale ha coinvolto numerose ed ulteriori prove di laboratorio, realizzate in ambito quasi-statico, su singoli elementi strutturali.L’esecuzione di prove di compressione ha permesso di verificare sia l’incremento di resistenza di tali elementi strutturali che la variazione delle loro modalità di rottura a seguito dell’iniezione di miscela legante. Ulteriori prove di taglio e compressione hanno fornito importanti indicazioni riguardo al comportamento meccanico di singoli elementi strutturali soggetti a forze cicliche nel piano. Infine, si è sviluppata una modellazione numerica del comportamento meccanico di campioni sottoposti a carico di compressione monoassiale. Quest'analisi ha dunque permesso di approfondire lo studio della distribuzione delle tensioni e delle modalità di rottura di singoli elementi strutturali, soggetti ad intervento di consolidamento mediante iniezioni di miscela legante.
33
Reza, Humayun. "Cleaning and restoring old masonry buildings : investigations of physical and chemical characteristics of masonry stones and clay bricks during cleaning." Thesis, Edinburgh Napier University, 2014. http://researchrepository.napier.ac.uk/Output/8851.
Full textAbstract:
Historic buildings and monuments are a precious finite asset and powerful reminders for future generations of the work and way of life of earlier cultures and civilisations. The stone cleaning and restoration of historic buildings is a crucial element in keeping the good look, integrity and quality of the fine art, method of construction and architecture of previous civilisations. Stone cleaning is one of the most noticeable changes a building can be subjected to, which changes its appearance, persona and environmental context. In this study, a series of physical and chemical tests were conducted to further investigate, evaluate and improve the efficiency of building cleaning. Seven different abrasives were adopted for air abrasive cleaning, including copper slag (fine, medium and coarse), recycled glass (fine, medium and coarse) and hazelnut/almond shell (natural abrasive), on a total of eight masonry stones and clay bricks, including yellow sandstone, red sandstone, limestone, marble, granite, white clay brick, yellow clay brick and red clay brick. Physical investigations included sieve tests and impact tests on the abrasives, greyscale image analysis, thickness reduction measurements, Vickers surface hardness tests, Charpy impact tests and water absorption tests. Chemical investigations included Scanning Electron Microscope (SEM) and Energy-Dispersive X-Ray Spectroscopy (EDX) analyses. Sieve tests and impact tests confirmed that the abrasives utilised were fairly reliable, and the abrasives with high bulk densities were stronger and tougher than those with low bulk density. Greyscale digital image analysis indicated a lower greyscale value corresponded to a dirtier masonry surface. In general, the greyscale continuously increased with the increasing cleaning time and tended to be stable when the surface became fully cleaned. The cleanness was also introduced for assessing the effectiveness of the building cleaning. Similar trends could be observed. Both parameters proved to be significantly useful. For most of the samples, monotonic increase trends were observed between the greyscale and thickness reduction. The image analysis on greyscale and the thickness measurement were two useful methods for assessing the cleaning degree of a masonry stone or clay brick. Based on the analysis on all the testing data, it is possible to recommend a more suitable abrasive for each masonry stone or brick. For granite and red clay brick, medium glass produced the best performance, while for limestone, marble and red sandstone, fine glass was promising. For yellow clay brick, fine slag could be the best option, while for yellow sandstone the natural abrasive was found to be the most suitable. vi The Vickers hardness test results indicated that a larger hardness corresponded to a harder masonry surface. Also the surface hardness continuously increased with the increasing cleaning time but at a decrease rate. Most of the increasing trends of the surface hardness could be approximately expressed using parabolic relationships. Granite was found to be the hardest, and followed by marble and limestone. However, there were no big differences in the surface hardness between yellow clay brick, yellow sandstone, red sandstone and white clay brick. The impact resistances of seven masonry stones and bricks were obtained by conducting the Charpy impact resistance tests. Granite showed the highest impact resistance among all the stones and bricks and was followed by marble, limestone, clay bricks and sandstones. The stones and bricks with higher impact resistances also had higher hardness values but lower water absorptions. The water absorbing capacity of the seven masonry stones and bricks was quantitatively determined. Two types of clay bricks showed the highest water absorptions, and the water absorptions for limestone, yellow sandstone and red sandstone were also quite high. However, the water absorption of marble and granite was found to be very low. Larger water absorption corresponded to a softer stone or brick, while smaller water absorption corresponded to a harder stone or brick. The chemical investigations by using the SEM and EDX techniques showed that the chemical substances on the masonry surface varied largely for different types of stones and bricks. This study showed the way to detect such soiling using chemical analysis by monitor the changes in chemical elements and compounds during the building cleaning. Finally, comprehensive conclusions were presented, together with useful suggestions for future work.
34
Teomete, Egemen Aktaş Engin. "Finite element modeling of historical masonry structures;case study: Urla Kamanli Mosque/." [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/insaatmuh/T000494.pdf.
Full text
35
Hrynyk, Trevor D. "Static evaluation of the out-of-plane behavior of URM infill walls utilizing modern blast retrofit systems." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.umr.edu/thesis/pdf/Hrynyk_09007dcc803bc4ce.pdf.
Full textAbstract:
Thesis (M.S.)--University of Missouri--Rolla, 2007.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed December 4, 2007) Includes bibliographical references (p. 184-186).
36
Tanner, Allison. "Strength of Masonry Grout Made with Expanded Shale." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4018.
Full textAbstract:
Light-weight aggregate has been used successfully for structural and non-structural applications, and its most common use has been in light-weight concrete. Limited research has been done on light-weight grout though and there are no standards in place. The research performed in this study is intended to increase the knowledge of light-weight grout specifically made with expanded shale aggregate. The research presented herein is a pilot study and consists of preliminary aggregate and grout testing that resulted in the mix design of six grout types: three fine grout designs and three coarse grout designs. Conventional normal-weight aggregate was employed in the first grout mix. A light-weight aggregate batch was made with the same material proportions, as well as the same target water-cement (w/c) ratio and cement content. The weight of the cement was increased by 30 percent in the third grout type of each set to determine the effect on strength. The slump, component temperature, unit weight, air content, segregation, cement content, w/c ratio, and compressive strength for each grout type was gathered throughout testing. Correlations between grout testing results are examined and discussed. In addition, the effectiveness of expanded shale grout, other light-weight grouts, and normal-weight grout with respect to compressive strength to cement content ratio are determined. Results of the testing show that all six grout types studied in this research reached the minimum 28-day strength of 13.8 MPa (2000 psi) ASTM standard. In addition, the results indicate that the cement content in expanded shale light-weight grout would need to be increased to reach comparable compressive strengths to that of the normal-weight grout. The comparison between the compressive strength to cement content ratio of the different grouts indicate that normal-weight grout is more efficient. In addition, light-weight grout made with blast furnace slag grout is slightly more efficient than that made with expanded shale; however, this observation was only possible after several crucial assumptions were made about an existing blast furnace slag study. These strength-cement ratios do not account, however, for the benefits of reduced dead loads, improved thermal insulation, and improved sound insulation that could potentially influence the choice of the material used in and the life-cycle cost of the construction. Additional research should be done to verify the results of the ratios and the assumptions made herein. Furthermore, a life-cycle analysis needs to be conducted before a definite conclusion is made about which type grout is more efficient.
37
Vorfolomeyeva, Yuliya. "Nonlinear static analysis of rubble-stone masonry buildings performed with equivalent frame method." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Find full textAbstract:
Nonlinear static analysis is an efficient tool for performance assessment of masonry structures. In particular, it facilitates the accurate prediction of seismic response of a structure to earthquakes. Numerical models based on Equivalent Frame Method allow to predict realistic failure modes observed after preceding seismic events with reasonable computational effort, a characteristic which is suitable for engineering practice. This thesis deals with nonlinear incremental static (pushover) analysis of masonry buildings and the subsequent discussion of the obtained results. TreMuri software is used for developing the numerical models, which are then analysed on the basis of elastic acceleration response spectra obtained according to the Nepal National Building Code. Different structural improvement techniques are implemented in the models and compared in order to determine their impact on seismic performance. Elastic stiffness obtained with the nonlinear analysis is examined in contrast to analytical estimation of the same, made with various mathematical models.
38
Mahmood, Hamid. "Seismic assessment and retrofit of unreinforced masonry buildings using fibre reinforced polymer materials." Thesis, University of Auckland, 2012. http://hdl.handle.net/2292/18034.
Full textAbstract:
The research in this thesis was conducted with the primary aims of seismically assessing the current stock of Pakistan unreinforced masonry (URM) buildings and investigating seismic retrofit of New Zealand URM buildings using fibre reinforced polymer (FRP) materials. Seismic assessment of Pakistan URM buildings was conducted by adopting three international rapid evaluation methods for Pakistan conditions. Assessment case studies of major cities of Pakistan were performed and it was concluded that the New Zealand method is applicable with certain modifications to Pakistan URM buildings. The focus of the second part of this research was on seismic retrofit of in-plane loaded walls, that are likely to fail in a shear mode, as such failures are commonly observed in earthquakes. FRP materials have become popular in recent years, but limited test data, and design guidelines exist for their use on URM walls. The experimental part of this included seventeen monotonic diagonal compression tests, six reverse cyclic diagonal compression tests, and six horizontal shear tests on unretrofitted and FRP-retrofitted walls. The research showed that FRP is highly effective in increasing shear strength, pseudo-ductility and toughness, which are important parameters in seismic design. Horizontal shear tests on flanged walls, with realistic boundary conditions, confirmed the effectiveness of FRP for enhancement of shear strength of URM. Simple finite element (FE) models were presented in this research using a commercial FE software. The models were effective in simulating the behaviour and shear stress of wallettes retrofitted with full surface fabrics and strips that were oriented along the wallette diagonals. A guide for the design of in-plane loaded walls that are retrofitted with externally bonded FRP materials was presented. Design expressions were developed from the basic principle and were correlated to the experimental results. Design examples were also included.
39
Dinu, Popa Emil Alexandru. "The energetic retrofit of historic masonry buildings : focus on Central and Northern Europe." Research Showcase @ CMU, 2010. http://repository.cmu.edu/theses/54.
Full textAbstract:
40% of the total energy consumed in Europe is consumed by building operation and usage (Itard, et al., 2008). In the temperate climate of central and northern Europe, a significant proportion of this consumption is attributed to building heating during the winter months. Although recent trends in European legislation favor an increase in thermal efficiency of building enclosures for new constructions, the majority of the building stock consists of buildings built to a lower standard of energy efficiency.
Over 56 % of the building stock in the central and northern European countries was built before 1970, when the first building energy efficiency regulations were adopted across Europe (Itard, et al., 2008). Even if current regulations require significant energy efficiency measures (EnEV 2009 in Germany requires a maximum heating energy consumption of 50 kWh/m2a) and the trend is to increase the standards even more, a vast portion of the building stock will have been built to much lower standards. Retrofitting existing buildings represents thus a priority, if a significant reduction in energy usage for buildings is to be achieved. There is a great opportunity in tackling this problem, especially when keeping in mind the fact that most of these inefficient building require significant renovation measures, as the lifespan of their systems comes to an end
The case of historic masonry buildings across Europe is especially relevant, as they pose special challenges related to the historic preservation of facades and even interiors. It is thus the aim of the present research to compile a set of principles and technologies that can be used for the thermal retrofit of historic buildings.
40
Brás, Xavier Helder Francisco. "The role of masonry infill in progressive collapse mitigation of multi-storey buildings." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/43154.
Full textAbstract:
The research presented in this thesis addresses the influence of non-structural masonry infill on the resistance of multi-storey buildings to progressive collapse under sudden column loss scenarios. In particular, the mechanical response of infilled frames in peripheral bays is investigated within the scope of a design-oriented robustness assessment framework. A ductility-centred progressive collapse assessment methodology recently developed at Imperial College is employed as a rational procedure to quantify structural robustness for sudden column loss. This allows due consideration of structural redundancy, ductility, strength, dynamic effects and energy absorption capabilities in a unified manner. In this way, robustness quantification is shifted from typical code recommendations into a sound performance-based mechanical assessment. The realistic contribution of masonry panels towards collapse arrest is examined considering the results from full-scale laboratory tests and accurate numerical simulations. Novel real-scale tests were performed on different two-bay frames with brick-masonry infill subjected to incremental pushdown deformation, capturing the dominant deformation mode actually found following removal of an edge column. In these physical tests, it was observed that the failure mechanisms and damage patterns displayed by the infilled frames under pushdown deformation are similar to those activated by lateral pushover loading. Chiefly, clear evidence of diagonal cracking and shear sliding, eventually culminating in crushing of the compressed corners were recorded during the tests. Different infill configurations were tested, including central openings and initial gaps between masonry and frame elements. Overall, a global stable response was observed even at the expense of severe damage in the masonry panels. Importantly, a monotonic supply of energy absorption was noticed with increasing vertical deformation, which translates into considerable robustness reserve associated with the confined infill walls. Secondly, advanced mesoscale finite element simulations were employed in order to capture the complex frame-infill interaction in the early stages of pushdown response, where it has been observed in a realistic case study that progressive collapse is effectively arrested at small dynamic deformations, with minimal damage to the masonry panels and surrounding structural elements. Finally, application of the robustness assessment framework allowed a critical comparison between the collapse resistance arising from secondary mechanisms typically considered in this context (such as floor membrane and beam catenary effects) and that related to the presence of masonry infill. While the former are quite effective at relatively large deformations, the latter is shown to add substantial contribution at small displacements. The conclusions in this thesis are particularly relevant within the context of retrofitting operations for robustness enhancement of existing structures, as a result of the growing demand for upgraded resilience of urban infrastructure. On the other hand, due account for masonry infill subject to proper quality control during the construction process is recommended for rational robustness design of new buildings.
41
Stefani, Francesca <1987>. "Seismic retrofit of existing RC and masonry buildings using external aluminium alloy exoskeleton." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amsdottorato.unibo.it/9875/1/Stefani_Francesca_tesi.pdf.
Full textAbstract:
This thesis is the result of the industrial PhD carried out in collaboration with Aliva S.r.l. company that develops customized solutions for ventilated facades. The ventilated façade is a multi-layer protective system for the building envelope where the light bearing structure is usually made of aluminium alloy for its property of lightness, durability, corrosion resistance, workability thanks to the extrusion process and eco-sustainability. The scope of this thesis is to investigate the use of aluminium alloys in application fields different from that of the ventilated façade. The use of aluminium alloys in structural engineering is a quite recent activity, because this family of materials is relatively new. Nowadays, after the several research carried out in order to characterize the design of aluminium alloys structures and the publication of Eurocode 9 Design of Aluminium Structures, there are many applications of aluminium alloys in structural engineering. However, there is still a lack of information about the ductility of this material and its use in seismic zones. In fact to date there is no seismic regulations for aluminium alloys applications, only recently in the project for the development of the next generation of structural Eurocodes, it was decided to introduce the aluminium alloys among the new emerging materials for anti-seismic structures. This thesis aims to make a contribution to the study of the possible use of aluminium alloys in seismic areas and intends to study if it can be a competitive solution in the seismic retrofit field. This study is part of the European research project Pro-GET-onE in which the Aliva company is involved together with the university of Bologna and other members. This thesis shows the study and the development of the design of an external structural frame, also called exoskeleton, made of aluminium alloys.
42
Rizzi, Ermes. "Role of timber in the seismic resilience of existing URM buildings." Doctoral thesis, Università degli studi di Trento, 2020. http://hdl.handle.net/11572/258047.
Full textAbstract:
The main topic of the thesis is the role of timber in the seismic resilience of unreinforced masonry (URM) buildings. The research addressed both existing timber components that can be encountered in URM buildings and timber-based retrofit solutions. The work presented herein can be split into two main phases.
In the first part of the research, the in-plane behavior of traditional wooden floors was analyzed by means of numerical static and dynamic simulations. Modelling strategies with different refinement levels were proposed and implemented to assess diaphragm in-plane strength and flexibility. Modelling was undertaken considering as-built diaphragms first and was then extended to diaphragms retrofitted by means of timber-based techniques. The influence of diaphragm construction details on their in-plane response was evaluated and timber-based retrofitting solutions were observed to be effective in mitigating in-plane diaphragm flexibility and in increasing in-plane diaphragm strength.
The second part of the PhD work was dedicated to investigate new retrofit solutions for URM buildings based on the use of engineered timber panels mechanically connected to the masonry. The first step saw the experimental testing of different types of timber-to-masonry connections considering both screw-type fasteners and adhesive anchors. In the second stage, full-scale masonry walls were tested in the as-built, retrofitted and repaired configurations, highlighting the benefits of the proposed technique on the in-plane response of the masonry walls.
43
Ceran, H. Burak. "Seismic Vulnerability Of Masonry Structures In Turkey." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612745/index.pdf.
Full textAbstract:
This study focuses on the evaluation of seismic safety of masonry buildings in Turkey by using fragility curves. Fragility curves for masonry buildings are generated by two behavior modes for load bearing walls: in-plane and out-of-plane. By considering the previous research and site investigations, four major parameters have been used in order to classify masonry buildings with in-plane behavior mode. These are number of stories, strength of load-bearing wall material, regularity in plan and the arrangement of walls (required length, openings in walls, etc.). In addition to these four parameters, floor type is also taken into account for the generation of fragility curves by considering out-of-plane behavior mode. During generation of fragility curves, a force-based approach has been used. In this study there exist two limit states, or in other words three damage states, in terms of base shear strength for in-plane behavior mode and flexural strength for out-of-plane behavior mode. To assess the seismic vulnerability of unreinforced masonry buildings in Turkey, generated fragility curves in terms of in-plane behavior, which is verified by damage statistics obtained during the 1995 Dinar earthquake, and out-of-plane behavior, which is verified by damage statistics obtained during the 2010 Elazig earthquake, is combined. Throughout the analysis, ground motion uncertainty, material variability and modeling uncertainty have also been considered. In the final part of the study, a single-valued parameter, called as &lsquovulnerability score&rdquo
, has been proposed in order to compare the seismic safety of unreinforced masonry buildings in Fatih sub province of Istanbul and to assess the influence of out-of-plane behavior together with the in-plane behavior of these existing masonry buildings.
44
Okail, Hussein. "Experimental and Analytical Investigation of the Seismic Performance of Low-Rise Masonry Veneer Buildings." Diss., [La Jolla] : University of California, San Diego, 2010. http://wwwlib.umi.com/cr/ucsd/fullcit?p.
Full textAbstract:
Thesis (Ph. D.)--University of California, San Diego, 2010.Title from first page of PDF file (viewed May 6, 2010). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 216-220).
45
Carloni, Federico. "A 3D model based on the SAM Method for seismic studies of masonry buildings." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/17151/.
Full textAbstract:
L'elaborato propone un metodo per la modellazione tridimensionale di interi edifici in muratura, con lo scopo di valutare le performance sismiche, mediante il programma di calcolo SAP2000. La metodologia proposta consente la modellazione di pareti in muratura simulandone il comportamento non lineare sotto azioni agenti nel piano ed allo stesso tempo permette di considerare la ripartizione delle azioni verticali e soprattutto orizzontali che avviene tra le pareti, dovuta alle zone di connessione, ai solai ed alla loro rigidezza a taglio nel piano. Per lo sviluppo del metodo di modellazione è stato utilizzato un edificio molto semplice. Successivamente la metodologia è stata applicata ad un caso più realistico sul quale si sono fatte anche considerazioni riguardo i diversi comportamenti della struttura in funzione della rigidezza dei solai.
46
Demirel, Ismail Ozan. "A Nonlinear Equivalent Frame Model For Displacement Based Analysis Of Unreinforced Brick Masonry Buildings." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612772/index.pdf.
Full textAbstract:
Although performance based assessment procedures are mainly developed for reinforced concrete and steel buildings, URM buildings occupy significant portion of building stock in earthquake prone areas of the world as well as in Turkey. Variability of material properties, non-engineered nature of the construction and difficulties in structural analysis of perforated walls make analysis of URM buildings challenging. Despite sophisticated finite element models satisfy the modeling requirements, extensive experimental data for definition of material behavior and high computational resources are needed. Recently, nonlinear equivalent frame models which are developed assigning lumped plastic hinges to isotropic and homogenous equivalent frame elements are used for nonlinear modeling of URM buildings.
The work presented in this thesis is about performance assessment of unreinforced brick masonry buildings in Turkey through nonlinear equivalent frame modeling technique.
Reliability of the proposed model is tested with a reversed cyclic experiment conducted on a full scale, two-story URM building at the University of Pavia and a dynamic shake table test on a half scale, two story URM building at the Ismes Laboratory at Bergamo. Good agreement between numerical and experimental results is found.
Finally, pushover and nonlinear time history analyses of three unreinforced brick masonry buildings which are damaged in 1995 earthquake of Dinar is conducted using the proposed three dimensional nonlinear equivalent model. After displacement demands of the buildings are determined utilizing Turkish Earthquake Code 2007, performance based assessment of the buildings are done.
47
Kim, Sang-Cheol. "Seismic assessment of low-rise shear wall buildings with non-rigid diaphragms." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/20755.
Full text
48
Doherty, Kevin Thomas. "An investigation of the weak links in the seismic load path of unreinforced masonary buildings /." Title page, table of contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phd655.pdf.
Full text
49
Ouyang, Yi, and 欧阳禕. "Theoretical study of hybrid masonry : RC structure behaviour under lateral earthquake loading." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hdl.handle.net/10722/196090.
Full textAbstract:
A confined masonry (CM) wall consists of a masonry wall panel surrounded by reinforced concrete (RC) members on its perimeters. Low-rise CM structures are widely used in earthquake-risked (EQ-risked) rural or suburban areas all over the world. Most of these structures fail in shear pattern under lateral EQ loads, and some of them collapse under a severe or even a moderate EQ due to inappropriate design. On the other hand, buildings constructed of RC frames have much better performance in resisting EQs, since their RC members have larger dimensions and heavier reinforcing ratios than those in CM structures. Nonetheless, RC-frame buildings are normally too expensive for most inhabitants in less developed regions.
In this study, as an improvement to the conventional CM buildings for EQ resistance and for the sake of post-EQ restoration, a hybrid masonry – RC (HMR) structure, whose working mechanism is different from that of a conventional CM structure, is proposed. The RC members (i.e. “tie beams” and “tie columns”), which function only as confinement in a CM building, will resist most of gravity load and part of lateral EQ load in an HMR structure, while the wall panels will take most of lateral EQ load and part of gravity load. This is achievable by slightly increasing the sizes and reinforcing ratios of RC members in HMR structures. Such buildings will not collapse in the absence of masonry wall panels because the gravity load bearing system is still intact. On the other hand, as the wall panels in the proposed HMR structure will absorb most of the energy induced by lateral EQ load, severe damages will be controlled within the wall panel region, so that only the wall panels need to be replaced instead of rebuilding the whole structure after the EQ event.
To investigate the mechanical behaviours of masonry assemblages to be used in HMR structures, a series of experimental tests were conducted. Having established the relevant material properties for HMR structures, finite element (FE) simulation was performed to verify its work mechanism.
Prior to applying the FE simulation to HMR structures, the FE technique was first applied to simulate the behaviours of two concrete-brick masonry panels under diagonal compression loading and a CM wall under cyclic lateral loading. The results show a good correlation between the experimental results and the simulated ones. This has validated the feasibility of using the FE software to study the proposed HMR structure.
The theoretical simulation results show that in a properly designed HMR wall, depending on the masonry reinforcing details and the boundary conditions of simulated load cases, about 70% of the gravity load imposed on the RC beam will be transferred to the RC columns and more than 80% of the seismic energy (in terms of strain energy) will be absorbed by the masonry panel. Therefore, it is obvious that the proposed HMR structure is very feasible to replace the conventional CM structure in resisting EQ attacks with no risk of collapse.published_or_final_version
Civil Engineering
Master
Master of Philosophy
50
De, la Harpe Charles William Henry. "The development of a seismic risk reduction procedure for the prioritization of low cost, load bearing masonry buildings." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97014.
Full textAbstract:
Thesis (MEng)--Stellenbosch University, 2015.ENGLISH ABSTRACT: The Western Cape is one of the most seismically active regions in South Africa. It features geological properties which can develop earthquakes as large as 6.87 on the Richter scale. This poses a serious threat to all of the buildings that are currently located within this region. A recent study has found that typical three-storey Unreinforced Masonry (URM) buildings in the Cape Town area shows a high probability of failure or damage if subjected to such a large earthquake. Many of these buildings can be found in an area of Cape Town called the Cape Flats, housing approximately 11 000 individuals. The structural integrity of these buildings are of concern to engineers since it houses a number of individuals. The purpose of the study was to develop a risk assessment procedure that could be used to assess low-rise multi-storey (2, 3 and 4 storeys) URM buildings in order to determine where the risk of earthquake related damage would be the highest. The risk assessment procedure compared various characteristics regarding the buildings, residents, seismic attributes of the region and the recovery capability of the residents. The result, in the form of a risk rating, enabled the buildings to be prioritized according to their seismic risk. The aim was to develop a comparative model which could be applied to a range of buildings, indicating where the impact of an earthquake would be greatest. This result could then be used for further remedial action (such as retrofitting) where it is needed the most. The risk assessment procedure used an Earthquake Risk Assessment Model (ERAM) which was specifically developed to assess the earthquake risk of each building with the use of 26 factors. These factors would each be individually scored and through the ERAM model would produce a risk rating. The buildings' can then be ranked (prioritized) according to it's risk rating to determine where remedial actions or procedures are needed first.
AFRIKAANSE OPSOMMING: Die Wes-Kaap is een van die mees seismiese aktiewe streke in Suid-Afrika. Dit bevat geologiese eienskappe wat aardbewings met groottes van 6,87 op die Richterskaal kan laat ontwikkel (1 in 475 jaar herhaal periode). Dit hou 'n bedreiging vir baie die geboue wat tans in hierdie streek geleë is. 'n Onlangse studie het bevind dat tipiese drie-verdieping lasdraende steengeboue in die omgewing van Kaapstad 'n hoë waarskynlikheid van faling of skade toon as dit blootgestel word aan 'n groot aardbewing. Baie van hierdie geboue kan gevind word in 'n gebied van Kaapstad genaamd die Kaapse Vlakte, wat vir ongeveer 11 000 individue behuising bied. Die strukturele integriteit van hierdie geboue is van belang aangesien dit 'n groot aantal individue huisves. Die doel van die studie was om 'n risiko-evaluerings proses te ontwikkel wat gebruik kan word om multi-verdieping (2, 3 en 4 verdiepings) lasdraende steengeboue te evalueer ten opsigte van aardbewing verwante skade. Die risiko-evaluering proses vergelyk verskeie kenmerke van die geboue, die inwoners, seismiese eienskappe van die streek en die vermoë van die inwoners om terug te keer na hul alledaagse leefstyl. Die resultaat is in die vorm van 'n risiko-gradering, wat die gebruiker in staat stel om die geboue te prioritiseer volgens hul aardbewings risiko. Die doel was om 'n vergelykende model te ontwikkel wat toegepas kan word om 'n verskeidenheid van geboue te evalueer, en aan te dui waar die impak van 'n aardbewing die grootste sal wees. Hierdie resultaat kan dan gebruik word vir verdere remediërende optrede of prosedures soos versterkings. Die risiko-evaluerings proses gebruik 'n "Earthquake Risk Assessment Model" (ERAM) wat spesifiek ontwikkel is om die aardbewings-risiko van elke gebou te evalueer met die gebruik van 26 faktore. Hierdie faktore word elkeen individueel beoordeel en 'n risiko-gradering word verkry met behulp van die ERAM model. Die geboue kan dan geprioritiseer word volgens elkeen se risiko-gradering om te bepaal waar daar remediërende optrede nodig is.