Дисертації з теми "High strength concrete Fire-testing"
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1
Mitchell, Andrew Douglass. "Shear friction behavior of high-strength concrete." Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/19274.
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Ezekiel, Samson. "Fire resistance simulation for high strength reinforced concrete." Thesis, London South Bank University, 2015. http://researchopen.lsbu.ac.uk/2084/.
Повний текст джерелаАнотація:
High strength reinforced concrete (HSRC) has been used more frequently in the construction of high rise buildings and other concrete structures in recent decades due to its advantages and excellent performance over normal strength and conventional reinforced concrete. Some of these advantages include: higher strength, better durability and allowance for provision of using less concrete and smaller section sizes. Although HSRC performs better than normal strength reinforced concrete (NSRC) at ambient temperatures, NSRC has been found to perform better than HSRC at elevated temperatures and fire conditions. Provision of adequate fire resistance for reinforced concrete (RC) structures is essential as fire represents an extreme loading and hazardous condition to which a structure might be exposed during its life span. The fire resistance of RC members is evaluated using a prescriptive approach which is irrational and conservative. Current codes of practice and construction in industry are moving towards performance based fire design method with computing software, which is a rationally based method with each structure designed to meets its own need. This method requires comprehensive knowledge and modelling of concrete and reinforcement material behaviour and their response at elevated temperatures. The fire resistance of HSRC members (columns and beams) in this study was evaluated using a three-dimensional Finite Element (FE) model created in ANSYS. The stress – strain behaviour of concrete proposed in this research was used in modelling the behaviour of concrete in ANSYS, while other concrete and steel material properties were accounted for by using models proposed by other researchers. The fire resistance of the HSRC members is evaluated using coupled field analysis (thermal – structural analysis) with performance based failure criteria provided in the code of practice. The accuracy of the FE model was verified by comparing the thermal response, structural response and predicted fire resistance with fire test results obtained. Using the validated FE model, parametric studies were conducted to investigate the influence of various parameters affecting the fire performance of HSRC members exposed to fire. From the parametric studies conducted, simplified calculation models were developed for evaluating the resistance of HSRC members (columns and beams) exposed to fire. These models were validated with results from ANSYS and a fire resistance test. The simple model accounts for major factors such as member size, load ratio and fire scenario, and therefore can be easily incorporated into structural design. The FE model and simple calculation model provide a rational approach for evaluating the fire resistance of HSRC (members) and predict a more accurate fire resistance than the prescriptive approach.
3
Zaina, Mazen Said Civil & Environmental Engineering Faculty of Engineering UNSW. "Strength and ductility of fibre reinforced high strength concrete columns." Awarded by:University of New South Wales. School of Civil and Environmental Engineering, 2005. http://handle.unsw.edu.au/1959.4/22054.
Повний текст джерелаАнотація:
The main structural objectives in column design are strength and ductility. For higher strength concretes these design objectives are offset by generally poor concrete ductility and early spalling of the concrete cover. When fibres are added to the concrete the post peak characteristics are enhanced, both in tension and in compression. Most of the available experimental data, on fibre reinforced concrete and fibre reinforced high strength concrete columns, suggest that an improvement in both ductility and load carrying capacity due to the inclusion of the fibres. In this thesis the ductility and strength of fibre reinforced high strength concrete are investigated to evaluate the effect of the different parameters on the performance of columns. The investigation includes both experimental and the numerical approaches with 56 high strength fibre reinforced concrete columns being tested. The concrete strength ranged between 80 and 100 MPa and the columns were reinforced with 1, 2 or 2.6 percent, by weight, of end hooked steel fibres. The effect of corrugated Polypropylene fibres on the column performance was also examined. No early spalling of the cover was observed in any of the steel fibre reinforced column tested in this study. A numerical model was developed for analysis of fibre and non-fibre reinforced eccentrically loaded columns. The column is modelled as finite layers of reinforced concrete. Two types of layers are used, one to represent the hinged zone and the second the unloading portion of the column. As the concrete in the hinged layers goes beyond the peak for the stress verus strain in the concrete the section will continue to deform leading to a localised region within a column. The numerical model is compared with the test data and generally shows good correlation. Using the developed model, the parameters that affect ductility in fibre-reinforced high strength concrete columns are investigated and evaluated. A design model relating column ductility with confining pressure is proposed that includes the effects of the longitudinal reinforcement ratio, the loading eccentricity and the fibre properties and content and design recommendations are given.
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Yosefani, Anas. "Flexural Strength, Ductility, and Serviceability of Beams that Contain High-Strength Steel Reinforcement and High-Grade Concrete." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4402.
Повний текст джерелаАнотація:
Utilizing the higher capacity steel in design can provide additional advantages to the concrete construction industry including a reduction of congestion, improved concrete placement, reduction in the required reinforcement and cross sections which would lead to savings in materials, shipping, and placement costs. Using high-strength reinforcement is expected to impact the design provisions of ACI 318 code and other related codes.
The Applied Technology Council (ATC-115) report "Roadmap for the Use of High-Strength Reinforcement in Reinforced Concrete Design" has identified key design issues that are affected by the use of high-strength reinforcement. Also, ACI ITG-6, "Design Guide for the Use of ASTM A1035 Grade 100 Steel Bars for Structural Concrete" and NCHRP Report 679, "Design of Concrete Structures Using High-Strength Steel Reinforcement" have made progress towards identifying how code provisions in ACI 318 and AASHTO could be changed to incorporate high-strength reinforcement.
The current research aims to provide a closer investigation of the behavior of beams reinforced with high-strength steel bars (including ASTM A615 Grade 100 and ASTM A1035 Grades 100 and 120) and high-strength concrete up to 12000 psi. Focus of the research is on key design issues including: ductility, stiffness, deflection, and cracking.
The research includes an extensive review of current literature, an analytical study and conforming experimental tests, and is directed to provide a number of recommendations and design guidelines for design of beams reinforced with high-strength concrete and high-strength steel. Topics investigated include: strain limits (tension-controlled and compression-controlled, and minimum strain in steel); possible change for strength reduction factor equation for transition zone (Φ); evaluation of the minimum reinforcement ratio (þmin); recommendations regarding limiting the maximum stress for the high-strength reinforcement; and prediction of deflection and crack width at service load levels. Moreover, this research includes long-term deflection test of a beam made with high grade concrete and high-strength steel under sustained load for twelve months to evaluate the creep deflection and to insure the appropriateness of the current ACI 318 time-dependent factor, λ, which does not consider the yield strength of reinforcement and the concrete grade.
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Dabbagh, Hooshang Civil & Environmental Engineering Faculty of Engineering UNSW. "Strength and ductility of high-strength concrete shear walls under reversed cyclic loading." Awarded by:University of New South Wales. School of Civil and Environmental Engineering, 2005. http://handle.unsw.edu.au/1959.4/27467.
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This study concerns the strength and behaviour of low-rise shear walls made from high-strength concrete under reversed cyclic loading. The response of such walls is often strongly governed by the shear effects leading to the shear induced or brittle failure. The brittle nature of high-strength concrete poses further difficulties in obtaining ductile response from shear walls. An experimental program consisting of six high-strength concrete shear walls was carried out. Specimens were tested under inplane axial load and reversed cyclic displacements with the test parameters investigated being longitudinal reinforcement ratio, transverse reinforcement ratio and axial load. Lateral loads, lateral displacements and the strains of reinforcement in edge elements and web wall were measured. The test results showed the presence of axial load has a significant effect on the strength and ductility of the shear walls. The axially loaded wall specimens exhibited a brittle behaviour regardless of reinforcement ratio whereas the specimen with no axial load had a lower strength but higher ductility. It was also found that an increase in the longitudinal reinforcement ratio gave an increase in the failure load while an increase in the transverse reinforcement ratio had no significant effect on the strength but influenced the failure mode. A non-linear finite element program based on the crack membrane model and using smeared-fixed crack approach was developed with a new aggregate interlock model incorporated into the finite element procedure. The finite element model was corroborated by experimental results of shear panels and walls. The finite element analysis of shear wall specimens indicated that while strengths can be predicted reasonably, the stiffness of edge elements has a significant effect on the deformational results for two-dimensional analyses. Therefore, to capture the deformation of walls accurately, three-dimensional finite element analyses are required. The shear wall design provisions given in the current Australian Standard and the Building Code of American Concrete Institute were compared with the experimental results. The comparison showed that the calculated strengths based on the codes are considerably conservative, specially when there exists the axial load.
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Meyer, Karl F. "Transfer and development length of 06-inch diameter prestressing strand in high strength lightweight concrete." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/20727.
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Islam, Md Shahidul. "Shear capacity and flexural ductility of reinforced high- and normal-strength concrete beams." Thesis, Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1766536X.
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Reutlinger, Christopher George. "Direct pull-out capacity and transfer length of 06-inch diameter prestressing strand in high-performance concrete." Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/19026.
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Shams, Mohamed Khalil. "Time-dependent behavior of high-performance concrete." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/20682.
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Chau, Siu-lee, and 周小梨. "Effects of confinement and small axial load on flexural ductility of high-strength reinforced concrete beams." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B31997661.
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Wong, Hin-cheong Henry, and 黃憲昌. "Effects of water content, packing density and solid surface area on cement paste rheology." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39326032.
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Wong, Kong-yeung, and 黃剛揚. "Development of high strength concrete for Hong Kong and investigation of their mechanical properties." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31213765.
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Inwood, Michael. "Review of the New Zealand Standard for Concrete Structures (NZS 3101) for High Strength and Lightweight Concrete Exposed to Fire." University of Canterbury. Civil Engineering, 1999. http://hdl.handle.net/10092/8276.
Повний текст джерелаАнотація:
This report describes the thermal properties, strength, and elastic modulus of lightweight, normal, and high strength concrete at elevated temperatures.
Section 6 (Design for Fire Resistance) of the New Zealand standard for concrete structure (NZS3101, 1995) provides recommended values and minimum requirements for concrete at elevated temperatures. These values will be reviewed with respect to overseas standards and experimental data to find their applicability to lightweight and high strength concretes.
A series of tests were performed on 1m x 1m lightweight and high strength concrete specimens to determine their insulation fire resistance. The specimens were produced in three thicknesses; 60, 130, and 175mm. This follows the method of earlier tests by Wade et al. (1991) and Wade (1992) on New Zealand aggregate concretes.
It was determined that the strength reduction curve given by NZS3101 over-predicts the strength of high strength concrete at elevated temperatures, though the values for elastic modulus and insulation fire resistance can be applied to high strength concrete.
The insulation fire resistance, strength, and elastic modulus values given by NZS3101 were found to also apply to lightweight concrete.
The report recommends a change to the elastic modulus curve given in NZS3101. The purpose of this is to give consistency between the strength and elastic modulus curves, which do not currently reach zero at the same temperature.
14
Lokuge, W. P. (Weena Priyanganie) 1967. "Stress-strain behaviour of confined high strength concrete under monotonically increasing and cyclic loadings." Monash University, Dept. of Civil Engineering, 2003. http://arrow.monash.edu.au/hdl/1959.1/9425.
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Kirchhof, Larissa Degliuomini. "Estudo teórico-experimental da influência do teor de umidade no fenômeno de spalling explosivo em concretos expostos a elevadas temperaturas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/32002.
Повний текст джерелаАнотація:
Os concretos de alta compacidade, com resistências elevadas (acima de 40 MPa), estão começando a ser cada vez mais usados em obras de infraestrutura e em edificações de grande porte, devido às importantes vantagens que os mesmos oferecem em termos de capacidade de carga e durabilidade. Um dos pontos acerca de seu desempenho que levanta dúvidas envolve o seu comportamento frente a elevadas temperaturas. Evidências coletadas em incêndios ocorridos em estruturas reais, como o do Channel Tunnel e do Mont Blanc Tunnel, indicaram que, sob certas circunstâncias, existe a possibilidade de ocorrência de um fenômeno, conhecido como spalling explosivo, que causa sérios danos por lascamento ao material, incrementando de forma significativa a degradação térmica. Isso ocorre porque a reduzida porosidade e a baixa permeabilidade favorecem o aprisionamento do vapor de água nos poros, gerando um acréscimo da pressão interna que ocasiona tensões que podem superar a resistência à tração do concreto. O processo de spalling, bem como a sua probabilidade e severidade de ocorrência, dependem de uma série de fatores interdependentes que influenciam o comportamento do material. Contudo, está se formando um consenso de que o teor de umidade é o parâmetro mais influente para o desencadeamento do processo. Estudos efetuados após o reconhecimento da existência do spalling explosivo demonstraram que o mesmo tende a ocorrer somente quando o concreto apresenta teores muito elevados de umidade em sua estrutura de poros. Isso restringe a preocupação a certos tipos de elementos onde o concreto pode estar muito úmido por ocasião do sinistro. Embora estes sejam casos raros, a gravidade dos danos devido ao spalling explosivo justifica que se investiguem as condições nas quais o mesmo pode acontecer e se implementem medidas mitigatórias. Dado o caráter recente das investigações sobre o tema, ainda existe uma carência de estudos específicos que apontem quais as combinações críticas de porosidade e teores de umidade que desencadeiam o fenômeno. Este trabalho foi concebido para ajudar a superar essa lacuna de conhecimento, coletando dados sobre as condições que favorecem o spalling explosivo, bem como averiguando quais são as propriedades mecânicas residuais e as alterações na microestrutura sofridas por concretos com vários patamares de resistência submetidos a altas temperaturas. O trabalho utiliza os dados coletados para fundamentar a proposição de um modelo simplificado de spalling, elaborado com o objetivo de prover uma forma de considerar os efeitos do fenômeno durante uma análise termomecânica. Essa é uma necessidade fundamental para complementar os softwares atualmente utilizados para analisar os efeitos de incêndios sobre estruturas. O módulo de spalling foi implementado computacionalmente de forma que pudesse ser utilizado em consórcio com a ferramenta computacional VULCAN, o que permitiu simular a ocorrência do fenômeno na deterioração de uma viga durante um incêndio. Os resultados indicaram que a perda de seção transversal causada pela ocorrência do spalling explosivo reduz substancialmente o tempo de resistência ao fogo (TRRF), devido à aceleração dos danos e à redução da capacidade portante dos elementos estruturais de concreto. Conclui-se, portanto, que é fundamental considerar a possibilidade de lascamentos explosivos em estruturas suscetíveis ao fenômeno. De acordo com o presente estudo, estas incluem aquelas fabricadas com concretos de resistência maior que 40 MPa, que apresentem grau de saturação em torno ou superiores a 90%.In the last years, the utilization of high-strength concrete (HSC) in the construction industry, with compressive strength grades greater than 40 MPa, has become wide spread due to remarkable characteristics of durability and load bearing capacity. However, the increased use of HSC has raised concerns regarding the behaviour of such concretes in fire. Evidences which were collected from structures exposed to the effects of fires, like Channel Tunnel and Mont Blanc Tunnel, have indicated that there is a possibility of the occurrence of explosive spalling in this condition. The phenomenon causes serious damages to the material and raises its thermal degradation in a significant way. This occurs because of its low porosity and permeability that contribute for the vapour pressure build-up in the pores, generating stresses which can exceed tensile strength of the material. The probability and severity of spalling process depend on a large number of inter-dependent factors that influence the behaviour of HSC in an unexpected manner. There is a consensus that the moisture content is one of the principal factors of the occurrence of explosive spalling. Recent investigations have demonstrated that spalling tends to occur only when the moisture content in the pores of concrete is elevated. Although fire is considered an exceptional event, the seriousness of spalling in concrete structures justifies the investigation of conditions in that the phenomenon can be happen and the implementation of preventive measures. In spite of the recent advances about the spalling process in HSC at high temperatures, there is still a lack of information in relation to the critical combinations of factors which affect the spalling occurrence. This work intends to help overcoming this lack of knowledge from the experimental data analysis with the purpose of establishing some critical conditions which collaborate in the spalling process as well as investigating the residual mechanical properties and changes in the microstructure of different concrete grades submitted to high temperatures. In addition, the experimental data are used to validate the proposition of a simplified model of spalling which was developed with the objective to take into account the effects of spalling in the thermo-mechanical analysis. This is an important need to complement the fire analysis of concrete structures. The spalling model was incorporated in the VULCAN software to simulate the phenomenon occurrence in a concrete beam exposed to fire. The results shown that the loss of mass in the beam cross-section, caused by spalling, reduces substantially its required time of fire resistance whereas it accelerates the damage in the concrete and aids the reduction of load bearing capacity of structural element. In conclusion, it is essential to consider the possibility of concrete spalling mainly in concrete grades greater than 40 MPa that present a saturation degree higher than 90%.
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Britez, Carlos Amado. "Avaliação de pilares de concreto armado colorido de alta resistência, submetidos a elevadas temperaturas." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3146/tde-31052011-170216/.
Повний текст джерелаАнотація:
Apesar da quantidade de variáveis envolvidas, ainda persiste uma dúvida na comunidade acadêmica sobre o comportamento do concreto de alta resistência em situação de incêndio, considerando-o como mais ou menos suscetível à ocorrência do fenômeno de desplacamento (spalling) tipo explosivo. Em parte, essa dúvida decorre do fato de que, muitas vezes, os programas experimentais são conduzidos em amostras envolvendo corpos-de-prova padronizados, cilíndricos ou cúbicos, que não levam em consideração a influência de parâmetros relacionados com as dimensões dos elementos estruturais nem com a taxa e configuração das armaduras. Outros aspectos relevantes, como o tipo de agregado utilizado na mistura de concreto, bem como a idade e umidade interna do elemento ensaiado, dificilmente são abordados nas pesquisas e, muitas vezes, simplesmente são omitidos, o que dificulta a visão ampla e real do comportamento térmico do concreto de alta resistência. Esta pesquisa apresenta um programa experimental pioneiro realizado no Brasil em um pilar de concreto de alta resistência, armado, colorido, com idade de oito anos, fc,8anos de 140MPa, agregado graúdo basáltico, agregado miúdo quartzoso, seção transversal de 70cm x 70cm, 200cm de altura, ensaiado sem carregamento e com exposição de três faces pelo período de 180 minutos (3h), sob as temperaturas da curva-padrão de incêndio ISO 834. O pilar protótipo ensaiado é réplica dos pilares reais do edifício e-Tower, construído em 2002, na cidade de São Paulo, Brasil. Os resultados obtidos demonstraram que, neste caso, o concreto colorido de alta resistência comportou-se de forma íntegra frente ao fogo e que a utilização de pigmento à base de óxido de ferro, pode atuar também como um excelente termômetro natural, auxiliando na avaliação da condição da estrutura pósincêndio.In spite of the several factors that influence the behavior of concrete columns under fire conditions, there is a belief among the research community, that the high-strength concrete is more susceptible to explosive spalling than normal-strength concrete. This doubt, in part, is attributed to the small unreinforced concrete samples (specimens) used in experimental programs, to evaluate the fire resistance of structural concrete. On the other hand, relevant aspects as the coarse aggregate type used in the concrete mixture, as well as the age and content moisture (relative humidity) are not considered in the researches and sometimes simply omitted. This research presents a pioneer experimental program, carried out in Brazil on a high strength colored reinforced concrete column (HSCC) with 200cm high, eight yearsold, fc,8years of 140MPa, basalt coarse aggregate, cross section of 700mm x 700mm, tested under no load and with three faces exposed to a standard fire curve ISO 834 for a period of 180min (3h). The column prototype is a replica of the actual columns of the e-Tower Building, constructed in 2002 in São Paulo city, Brazil. The results demonstrated concrete column integrity under experimental fire and that the iron oxide pigments can work as an excellent natural thermometer, contributing in the evaluation of the structure post-fire.
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Ghasemi, Sahar. "Innovative Modular High Performance Lightweight Decks for Accelerated Bridge Construction." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/2248.
Повний текст джерелаАнотація:
At an average age of 42 years, 10% of the nation’s over 607,000 bridges are posted for load restrictions, with an additional 15% considered structurally deficient or functionally obsolete. While there are major concerns with decks in 75% of structurally deficient bridges, often weight and geometry of the deck further limit the load rating and functionality of the bridge. Traditional deck systems and construction methods usually lead to prolonged periods of traffic delays, limiting options for transportation agencies to replace or widen a bridge, especially in urban areas.
The purpose of this study was to develop a new generation of ultra-lightweight super shallow solid deck systems to replace open grid steel decks on movable bridges and as well serve as a viable alternative in bridge deck replacements across the country. The study has led to a lightweight low-profile asymmetric waffle deck made with advanced materials. The asymmetry comes from the arrangement of primary and secondary ribs, respectively perpendicular and parallel to the direction of traffic. The waffle deck is made with ultrahigh performance concrete (UHPC) reinforced with either high-strength steel (HSS) or carbon fiber reinforced polymer (CFRP) reinforcement. With this combination, the deck weight was limited to below 21 psf and its overall depth to only 4 inch, while still meeting the strength and ductility demands for 4 ft. typical stringer spacing. It was further envisioned that the ultra-high strength of UHPC is best matched with the high strength of HSS or CFRP reinforcement for an efficient system and the ductile behavior of UHPC can help mask the linear elastic response of CFRP reinforcement and result in an overall ductile system. The issues of consideration from the design and constructability perspectives have included strength and stiffness, bond and development length for the reinforcement, punching shear and panel action. A series of experiments were conducted to help address these issues. Additionally full-size panels were made for testing under heavy vehicle simulator (HVS) at the accelerated pavement testing (APT) facility in Gainesville. Detailed finite element analyses were also carried out to help guide the design of this new generation of bridge decks. The research has confirmed the superior performance of the new deck system and its feasibility.
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Leite, Junior Geraldo Silveira. "Colunas mistas esbeltas de aço preenchidas com concreto de alta resistencia em temperatura ambiente e em situação de incendio." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258263.
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Orientador: Armando Lopes Moreno JuniorTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
Made available in DSpace on 2018-08-13T04:09:02Z (GMT). No. of bitstreams: 1 LeiteJunior_GeraldoSilveira_D.pdf: 5865663 bytes, checksum: d49ee862fe97f6a26434a033e8947468 (MD5) Previous issue date: 2009
Resumo: Neste trabalho, foi investigado em laboratório o efeito do fogo em colunas esbeltas de aço sem preenchimento e preenchidas com concreto de alta resistência que foram submetidas a três diferentes níveis de carga (30%, 50% e 70%). O nível de carga é a razão entre a carga axial a ser aplicada em situação de incêndio e a carga última obtida no ensaio da coluna à temperatura ambiente. Assim sendo, colunas esbeltas de aço sem preenchimento e preenchidas com concreto de alta resistência também foram investigadas à temperatura ambiente, uma vez que os resultados obtidos nessa situação serviram de referência para o estabelecimento das cargas axiais que foram aplicadas em situação de incêndio. Ao todo, foram investigadas 32 colunas esbeltas, sendo 4 sem preenchimento e 4 preenchidas com concreto de alta resistência em temperatura ambiente. Além dessas colunas, 12 foram ensaiadas sem preenchimento e 12 preenchidas com concreto de alta resistência em situação de incêndio. Os valores experimentais de carga última obtidos com as colunas de aço sem preenchimento e preenchidas com concreto de alta resistência à temperatura ambiente e em situação de incêndio foram comparados a aqueles determinados a partir da formulação proposta respectivamente pelo EUROCODE 3 (prEN 1993-1-1:2001), EUROCODE 4 (prEN1994-1-1:2003), EUROCODE 3 (prEN 1993-1-2:2002) e pelo EUROCODE 4 (prEN1994-1-2:2002), além de outras propostas de pesquisadores que foram encontradas na escassa literatura sobre o assunto. Como parte numérica, os resultados obtidos para as colunas mistas em situação de incêndio foram comparados a aqueles determinados por meio da utilização de dois softwares, que foram o SuperTempCalc e o PotFire. Ao final, observou-se que o preenchimento das colunas esbeltas de aço com concreto de alta resistência, propiciou melhorias significativas no tempo de resistência ao fogo dessas colunas, porém, comprovou-se que, de forma geral, somente as colunas em situação de incêndio que atingiram o tempo mínimo de resistência ao fogo, estipulado tanto no EUROCODE 4 (prEN 1994-1-2:2002), quanto na NBR 14432 (2000) em 30 minutos, foram as que apresentaram os resultados mais satisfatórios.
Abstract: In this work, it was investigated in laboratory the effect of fire in slender steel columns unfilled and filled with high strength concrete submitted to three different levels of axial load (30%, 50% and 70%), which is the relation between the axial load to be applied in fire situation and the ultimate load obtained in the column test to room temperature. So, slender steel columns unfilled and filled with high strength concrete were also investigated to room temperature, once the results obtained in this situation have served of reference to the establishment of axial loads applied in fire situation. Altogether 32 slender columns were tested, being 4 unfilled and 4 filled with high strength concrete in room temperature. Besides these columns, 12 were tested filled with high strength concrete in fire situation and 12 unfilled. The experimental values of ultimate load obtained with steel columns unfilled and filled with high strength concrete to room temperature and in fire situation were compared to those determinated from the formulation proposed by EUROCODE 3 (prEN 1993-1-1:2001), EUROCODE 4 (prEN1994-1-1:2003), EUROCODE 3 (prEN 1993-1-2:2002) and EUROCODE 4 (prEN1994-1-2:2002), besides others researchers' proposals found in scarce literature about the subject. As a numeric part, the results obtained for mixed columns in fire situation were compared to those determinated by means of using two softwares, the SuperTempCalc and the PotFire. At the end, it was observed that the filling of slender steel columns with high strength concrete have provided significant improvement in the time of resistance to fire in these columns, but it was proved that, in general, only the columns in fire situation which reached the minimum time to fire resistance, stipulated in EUROCODE 4 (prEN 1994-1-2:2002), as in NBR 14432 (2000) in 30 minutes, were the ones that have presented the most satisfactory results.
Doutorado
Estruturas
Doutor em Engenharia Civil
19
Arakelian, Andrea Katherine. "Strength analysis of bolted shear connections under fire conditions using the finite element approach." Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-122208-145717/.
Повний текст джерела
20
Procházka, David. "Vytvoření předpokladů pro hodnocení vlastností vysokopevnostních betonů s využitím nedestruktivních metod zkoušení." Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-233795.
Повний текст джерелаАнотація:
High-strength concrete (HSC) belongs in the recent years to frequently used types of concrete. It allows realization of static challenging structures and also shows due to its dense structure greater durability especially against aggressive media. Currently HSC construction realization abroad is not exceptional. It’s using in the Czech Republic is still limited. When realized, then in a small scale in civil engineering works. The realization of high-strength concrete structures is closely related with the concrete construction quality verification. Good efficiency of the quality control methods can provide non-destructive testing methods (NDT), especially when investigating strength of concrete built in structure. A lack on relevant data for non-destructive testing of HSC in technical and normative rules is to be considered as a significant deficiency. Evident for HSC generally is the lack in literature on deeper analysis of the factors affecting their non-destructive testing, as well a meaningful methodology or practically usable calibration relationships. HSC differs from ordinary concrete not only by used components, but also by more compact structure with different strength – elastic characteristics. Considering these differences, HSC strength prediction can not be performed by using calibration relationships developed for ordinary concrete. Moreover, the question is to what extent the current knowledge of the NDT results influencing factors can be considered as valid. The paper presents findings on the effects of the key factors affecting the measurement results of Schmidt hardness method and ultrasonic pulse method, including recommendations for the practical application of these methods. The problematic of static vs. dynamic modulus of elasticity was also solved. Calibration equations for predicting the compressive strength of HSC from the non-destructive testing parameter were elaborated, showing high cohesion among variables and practically usability.
21
Maluk, Cristian. "Development and application of a novel test method for studying the fire behaviour of CFRP prestressed concrete structural elements." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/15926.
Повний текст джерелаАнотація:
A novel type of precast, prestressed concrete structural element is being implemented in load-bearing systems in buildings. These structural elements combine the use of high-performance, self-consolidating concrete (HPSCC) and non-corroding carbon fibre reinforced polymer (CFRP) prestressing tendons; this produces highly optimized, slender structural elements with excellent serviceability and (presumed) extended service lives. More widely, the use of new construction techniques, innovative materials, and ground-breaking designs is increasingly commonplace in today's rapidly evolving building construction industry. However, the performance of these and other structural elements in fire is in general not well known and must be understood before these can be used with confidence in load-bearing applications where structural fire resistance is a concern. Structural fire testing has traditionally relied on the use of the standard fire resistance test (i.e. furnace test) for assuring regulatory compliance of structural elements and assemblies, and in many cases also for developing the scientific understanding of structural response to fire. Conceived in the early 1900s and fundamentally unchanged since then, the standard testing procedure is characterized by its high cost and low repeatability. A novel test method, the Heat-Transfer Rate Inducing System (H-TRIS), resulting from a mental shift associated with controlling the thermal exposure not by temperature (e.g. temperature measured by thermocouples) but rather by the time-history of incident heat flux, was conceived, developed, and validated within the scope of the work presented in this thesis. H-TRIS allows for experimental studies to be carried out with high repeatability, imposing rationally quantifiable thermal exposure, all at low economic and temporal cost. The research presented in this thesis fundamentally seeks to examine and understand the behaviour of CFRP prestressed HPSCC structural elements in fire, with emphasis placed on undesired 'premature' failure mechanisms linked to the occurrence of heat-induced concrete spalling and/or loss of bond between the pretensioned CFRP tendons and the concrete. Results from fire resistance tests presented herein show that, although compliant with testing standards, temperature distributions inside furnaces (5 to 10% deviation) appear to influence the occurrence of heat-induced concrete spalling for specimens tested simultaneously during a single test; fair comparison of test results is therefore questionable if thermal exposure variability is not explicitly considered. In line with the aims of the research presented in this thesis, H-TRIS is used to carry out multiple comprehensive studies on the occurrence of concrete spalling and bond behaviour of CFRP tendons; imposing a quantified, reproducible and rational thermal exposure. Test results led to the conclusion that a "one size fits all" approach for mitigating the risk of heat-induced concrete spalling (e.g. prescribed dose of polypropylene (PP) fibres included in fresh concrete), appears to be ineffective and inappropriate in some of the conditions examined. This work demonstrates that PP fibre cross section and individual fibre length can have an influence on the risk of spalling for the HPSCC mixes tested herein. The testing presented herein has convincingly shown, for the first time using multiple repeated tests under tightly controlled thermal and mechanical conditions, that spalling depends not only on the thermal gradients in concrete during heating but also on the size and restraint conditions of the tested specimen. Furthermore, observations from large scale standard fire resistance tests showed that loss of bond strength of pretensioned CFRP tendons occurred at a 'critical' temperature of the tendons in the heated region, irrespective of the temperature of the tendons at the prestress transfer length, in unheated overhangs. This contradicts conventional wisdom for the structural fire safety design of concrete elements pretensioned with CFRP, in which a minimum unheated overhang is generally prescribed. Overall, the research studies presented in this thesis showed that a rational and practical understanding of the behaviour of CFRP prestressed HPSCC structural elements during real fires is unlikely to be achieved only by performing additional standard fire resistance tests. Hence, H-TRIS presents an opportunity to help promote an industry-wide move away from the contemporary pass/fail and costly furnace testing environment. Recommendations for further research to achieve the above goal are provided.
22
Pessôa, José Renato de Castro. "Análise numérico-experimental de estruturas de concreto com utilização da energia de fraturamento." Universidade do Estado do Rio de Janeiro, 2007. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=780.
Повний текст джерелаАнотація:
Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorA evolução dos concretos utilizados nas últimas décadas deu origem ao Concreto de Alto Desempenho (CAD), que tem, entre suas características, alta resistência à compressão e baixa permeabilidade. Com o desenvolvimento dos produtos químicos utilizados na construção civil, em especial os superplastificantes e superfluidificantes, a utilização desse tipo de concreto tornou-se cada vez mais freqüente pela possibilidade de se obter uma mistura suficientemente trabalhável utilizando-se fatores água/cimento menores do que 0,35. Devido à sua microestrutura mais homogênea, esse tipo de concreto apresenta um comportamento mais frágil do que os concretos convencionais, exigindo uma melhor caracterização do material. A partir do final da década de 70 começou-se a aplicar os conceitos da Mecânica da Fratura para análise do comportamento de estruturas construídas com esse tipo de concreto. Como em algumas situações a resistência nominal de peças de concreto diminui com o aumento de suas dimensões, houve a necessidade de se considerar o efeito de escala das estruturas a fim de se obter níveis de segurança mais adequados no seu dimensionamento, o que justificou a utilização da Mecânica da Fratura. Neste trabalho a energia de fraturamento foi obtida experimentalmente pelo método do trabalho de fraturamento e pelo método do efeito de escala, por meio de ensaios estáveis de flexão de três pontos em amostras de concreto de alto desempenho com entalhe. Foi também desenvolvida a simulação numérica de uma viga com entalhe, analisada pelo método dos elementos finitos e empregando-se na modelagem constitutiva os conceitos da Mecânica da Fratura aplicada ao concreto. As vigas foram moldadas e ensaiadas no Instituto Politécnico do Rio de Janeiro (IPRJ) da Universidade do Estado do Rio de Janeiro (UERJ) na cidade de Nova Friburgo. Os ensaios foram realizados com controle de deslocamento da célula de carga. Foram ensaiadas três séries de 12 vigas, com quatro dimensões diferentes, geometricamente proporcionais, e três amostras para cada dimensão, totalizando 36 vigas. As alturas utilizadas para as vigas foram 38, 76, 152 e 304 mm, e sua espessura foi mantida constante igual a 38 mm. Os corpos de prova cilíndricos, para caracterização da resistência à compressão do concreto, foram moldados no IPRJ e rompidos no laboratório de engenharia civil da UERJ, na cidade do Rio de Janeiro. Os concretos utilizados apresentaram resistência à compressão média de 70 MPa.
The evolution of the concrete mixes used during the last decades gave birth to the High Performance Concrete (HPC), which, among its main characteristics, presents high strength and low permeability. With the development of chemical products used in civil engineering constructions, mainly the superplasticizers, the use of this kind of concrete has become more and more frequent due to the possibility of obtaining a workable mixture with a water/cement ratio lower than 0.35. Due to its more homogeneous microstructure, the HPC presents a more fragile behavior than the conventional concrete, demanding a better characterization of the material. At the end of the 1970s, concepts of the Fracture Mechanics started to be used for the analysis of the structural behavior of concrete structures. As the nominal stress of the material decreases as the size of the structure increases, it became necessary to consider this size effect in the analysis in order to obtain more suitable levels of security. This fact justifies the use of the Fracture Mechanics in the structural analysis of concrete structures. In this work, the fracture energy was experimentally obtained using the work-offracture method and the size effect method by performing three-point bend tests in HPC notched beams. It was also developed a numerical simulation of the tests, performing the analysis through the Finite Element Method and applying the concepts of the Fracture Mechanics of Concrete into the constitutive model. The notched beams were molded and tested at the Polytechnic Institute of the State University of Rio de Janeiro (IPRJ/UERJ), located in the city of Nova Friburgo. The tests were controlled by the vertical displacement of the load cell. Three series of twelve beams with four geometrically similar sizes were tested. Three samples for each size were cast, making an amount of 36 beams. The beams were 38, 76, 152 and 304 millimeters high and the width was kept constant equal to 38 millimeters. To characterize the concrete compression strength, 100x200 millimeters cylinders were molded at the IPRJ and tested at the UERJ civil engineering laboratory in the city of Rio de Janeiro. The tested concretes presented a medium compressive strength of 70 MPa.
23
Lu, Tien Tsai, and 盧天財. "Study on High Strength Fiber Concrete Slab Exposed to Fire." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/77096362394191645597.
Повний текст джерелаАнотація:
碩士國立交通大學
土木工程系
91
Recently, the use of high strength concrete (HSC) in high rise building was increased significantly. Therefore, the endurance capability of HSC at elevated temperature was an important research topic. Series study were conducted in our campus for HSC at elevated temperature. The study of mechanical behavior of slab at elevated temperature will be included in proposal. The adding of fibers to increase the ductility of HSC will be investigated too. The effect of adding fibers, strength concrete will be tested to compared with the results from HSC. Whole study will be under the guide line of ASTM E119 and ACI216. Simple supported slab with will be studies. The distribution of temperature inside of slab and the deflection of slab will be measured in the progress of tests.
24
Espinos, A., M. L. Romero, and Dennis Lam. "Fire performance of innovative steel-concrete composite columns using high strength steels." 2016. http://hdl.handle.net/10454/8142.
Повний текст джерелаАнотація:
yesThis paper presents the results of a numerical investigation on strategies for enhancing the fire behaviour of concrete-filled steel tubular (CFST) columns by using inner steel profiles such as circular hollow sections (CHS), HEB profiles or embedded steel core profiles. A three-dimensional finite element model is developed for that purpose, which is capable for representing the various types of sections studied and the nonlinear behaviour of the materials at elevated temperatures. High strength steel is considered in the numerical model, as a possible way to lengthen the fire endurance. The numerical model is validated against experimental results available in the literature for various types of steel-concrete composite sections using inner steel profiles, obtaining satisfactory results. Based on the developed numerical model, parametric studies are conducted for investigating the influence of the cross-sectional geometry and the steel grade of the inner profiles on the fire performance of these composite columns, for eventually providing some practical recommendations.
25
劉靖國. "Flexural behaviors of reinforced high-strength concrete beams after exposure to fire." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/57982472816900674919.
Повний текст джерела
26
Jheng, Guan-wei, and 鄭冠威. "Effect of Fire on Compressive Strength of Early Cured High Performance Concrete." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/80688395868400507545.
Повний текст джерелаАнотація:
碩士國立高雄第一科技大學
環境與安全衛生工程研究所
100
This study investigated the effect of high temperature on early cured concrete with and without fly ash (w/c=0.5). Parameters studied included the ratio of fine/coarse aggregates (1:1 and 1.5:1), curing duration (3, 7, 14, 28 and 56 days), exposure temperature (300℃, 450℃, 600℃ and 850℃). After specimens were exposed to the high temperatures, residual compressive strength test (RCS) and ultrasonic pulse velocity test (UPV) were carried out on the next day, 35th day after casting and 21-day recurring. The data shows that the UPV decreased for all specimens after exposed to high temperature, and the reduction was more significant for specimens with higher temperature. Internal structural damage caused by the high temperature lowered their densities. In addition, the RCS of normal concrete significantly rose after the concrete exposed to 450℃. The rise was attributed to the evaporation of free water and crystallization water, and then transportation of moisture in concrete. The high temperatures accelerated hydration at the early stage of concrete. Furthermore, the compressive strength at 450℃ decreased for the fly ash concrete. Because fly ash concrete has low permeability and high density, water vapor did not easily dissipate, increasing the pore pressure and eventually leading the production of microcracks. Additionally, insignificant recovery of the UPV and RCS after post-fire-curing existed. Moisture supply with air-curing to continue and expedite the rehydration reactions was not effective.
27
Yeh, Ming-Jia, and 葉明家. "The Effects of Fire-Retardant Coating on Strength of Concrete under High Temperature." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/56898374716502358124.
Повний текст джерелаАнотація:
碩士國立屏東科技大學
土木工程系所
98
Student ID: N9633018 Title: The Effects of Fire-Retardant Coating on Strength of Concrete under High Temperature Pages: 49 Name of Institute: National Pingtung University of Science and Technology Name of Department: Department of Civil Engineering Date of Graduation: January 2010 Degree Conferred: Master Name of student: Ming-Jia Yeh Adviser: Dr. Jun-Kai Lu Abstract content: Fire-Retardant Coatings are used wildly in wooden building, steel structures and interior partitions. It is hardly used in concrete structure. The concrete are very popular material for structure in Taiwan. The mechanical behaviors of concrete are changing with respected to the changing of temperature. Present paper investigates the effects of the Fire-Retardant Coating on strength of concrete under high temperature. Three different Fire-Retardant Coatings are investigated. Five different temperatures are discussed in present paper. There are room temperature, 400℃,500℃,600℃,700℃. It is shown that the strength of concrete specimen with Fire-Retardant Coating are high than the strength of concrete specimen without fire-retardant coating. Also, the strength of concrete specimen with different fire-retardant coating is different from each other.
28
Wu, Miin Chyi, and 吳敏祺. "Factors affect the spalling behavior of high strength concrete in fire and its material properties after fire." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/41229957923159006925.
Повний текст джерела
29
HUANG, PO-CHIA, and 黃柏嘉. "Seismic Testing of High-Strength Reinforced Concrete Exterior Beam-Column-slab connections." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/49818516948465088936.
Повний текст джерелаАнотація:
碩士國立雲林科技大學
營建工程系
104
To study the degradation of joint shear strength, this paper designed four New RC exterior beam-column connections with slabs and transverse beams covers 2/3 or 3/4 width of the joint face using current codes. Four beam-column connections were made with 70 MPa concrete, SD685 longitudinal reinforcement and SD785 transverse reinforcement. Test results showed that the current ACI 318 code is conservative. The transverse beams which covered 2/3 width of the joint face still had some confining effect to enhance the joint shear strength. Typical pushover analysis use beam-column centerline models with rigid joints, which may get unconservative results. This paper also presents nonlinear modeling of the joint with two equivalent compression struts using a commercial structural analysis tool. Following the recommendations of ASCE 41 and ACI 369, the joint keep elastic if the shear demand is less than the nominal shear strength. This paper propose to model the joint shear failure after beam yielding. Using empirical formula obtained by prior database investigation, the joint nonlinear springs are adjusted according to the prediction of failure mode. The proposed skills can improve the results of pushover analysis and well predict the envelopes for the cyclic loading test results. Further calibration and verification of the modeling parameters are recommended to widely use in practice.
30
Liu, Wen-hao, and 柳文皓. "Seismic Testing of High-Strength Reinforced Concrete Interior Beam-Colunm-slab connections." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/z9fj97.
Повний текст джерелаАнотація:
碩士國立雲林科技大學
營建工程系
104
For high-rise buildings, columns made of normal-strength reinforced concrete have large cross-sectional dimensions which cannot be accepted by end users. Using high-strength reinforcement and concrete have many advantages, including smaller member sizes, lighter structure elements, lesser steel reinforcement, longer span capability, and more space available for end users. This paper presents experiments of the sub-project “behavior, design, and modeling of new RC frame joints subjected to seismic loading” in the Taiwan New RC Project. Four new RC interior beam-column connections with transverse beams and slabs were tested according to the acceptance criteria for moment frames, evaluating the effect of transverse beams covers 1/2 or 3/4 width of the joint face. The degradation of the joint shear strength is also investigated. Four beam-column connection specimens were made with 100-MPa concrete, SD685 longitudinal reinforcement, and SD785 transverse reinforcement. Two connection specimens have precast concrete units with cast-in-place concrete joint and slabs, while the other two specimens are monolithic beam-column-slab connections. Test results show that the precast beams and columns with cast-in-place concrete joint perform as well as expected for seismic design of moment frames. Test results shows that the 1/2-column-width-wide transverse beams still have partial confinement effect. It is recommended that the nominal joint strength between calculated by linear interpolation between 1.25√(f_c^' ) MPa(15√(f_c^' ) psi) and 1.67√(f_c^' ) MPa(20√(f_c^' ) psi) for transverse beams cover 1/2 and 3/4 width of the column, respectively.
31
EN, LEE CHEN, and 李承恩. "The Effects of Fire Resistance Materials on Strength of Concrete and Bonding Strength of Rebar under High Temperature." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/69vhk8.
Повний текст джерелаАнотація:
碩士逢甲大學
土木工程學系
107
This study is to investigate the difference in compressive strength and the bonding strength between concrete specimens and specimens coated with fire resistance material under various fire temperatures. There are a total of 84 concrete cylindrical specimens with dimensions of ∅12cm×24cm, in which 21 specimens are embedded with 22 cm length of #4 rebar and 24 specimens with different embedment length of #3 rebar, all with design strength of 245 kgf/〖"cm" 〗^"2" . The experimental parameters include the thickness of fire resistance material coating, fire temperature, and fire exposure duration. The concrete compression test and pullout test of concrete specimens and reinforced concrete specimens are made after the specimens are exposed to fire. From the test results, the compressive strength of concrete cylindrical specimen decreases less as the thickness of fire resistance material increases, with a better fire protection effect. The pullout strength of reinforced concrete specimen drops less as the thickness of fire resistance material increases, with a better bonding strength protection effect. The results also show that the pullout strength of the specimen coated by the fire resistance material increases as the embedment length of rebar increases after being heated, with a better bonding force protection effect.
32
Wu, Y. F. (Yu-Fei). "Seismic retrofitting of rectangular reinforced concrete columns with partial interaction plating." 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phw9591.pdf.
Повний текст джерела
33
Wu, Y. F. (Yu-Fei). "Seismic retrofitting of rectangular reinforced concrete columns with partial interaction plating / by Yu-Fei Wu." Thesis, 2002. http://hdl.handle.net/2440/21836.
Повний текст джерелаАнотація:
"June 2002"Includes bibliographical references (leaves 349-374)
xxxix, 416 leaves : ill., plates ; 30 cm.
Thesis (Ph.D.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 2002
34
Clark, W. S. "Axial load capacity of circular steel tube columns filled with high strength concrete." Thesis, 1994. https://vuir.vu.edu.au/18153/.
Повний текст джерелаАнотація:
This study examines the axial load capacity of circular Concrete Filled Steel Tube
columns using High Strength Concrete (CFST-HSC). Emphasis is drawn to the
enhanced axial capacity of short columns attributed to the lateral confinement of the
concrete infill provided by the steel encasement. The degree of confinement has been
found to be dependent on several geometric and mechanical parameters. At present,
significant discrepancies exist with respect to quantifying the effective strength confined concrete. Existing design models and codes are predominantly derived from
the characteristics of normal strength concrete and therefore may be inappropriate concrete filled steel columns utilising High Strength Concrete (HSC).
An extensive experimental program was initiated to examine the axial capacity of
CFST-HSC columns. The results of 62 concentrically loaded scale model columns filled
with High Strength Concrete (46-100 MPa) are presented. The principal experimental
parameters were concrete and steel strengths, tube diameter to wall thickness ratio, column slenderness ratio. The columns tested were classified as short thin walled
sections and were tested as isolated column elements under short term loading. The
results are compared with the predictions of several existing design procedures and
recommendations are proposed.
35
Hsiao, Cheng-Chieh, and 蕭政杰. "Nondestructive testing and evaluation of the residual strength and material properties of fire-damaged slag concrete." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/26166237827463160812.
Повний текст джерелаАнотація:
碩士國立中興大學
土木工程學系所
99
The effects of the fire on safety and durability of concrete structures is profound. This study focuses on the slag concrete with a slag replacement of 60%, and uses different curing methods under different curing periods after the concrete exposed to high temperature for two hours. This research is to investigate the relationship between residual velocity and residual strength by using the ultrasonic pulse velocity method and the impact-echo method. Furthermore, to explore the relationship among heating temperature and the residual strength ration, residual density ration, the residual Poisson ration, the residual static elastic modulus, residual dynamic elastic modulus of slag concrete under fire damage. According to the experimental results, the reduction in residual strength of slag concrete is significant at the temperature over 600 ℃. And the fire-damaged concrete has a better recovery after water-curing, rather than air curing condition. The two aforementioned methods are used to investigate the relationship between residual velocity and residual compressive strength of fire-damaged concrete under different curing conditions. The result also shows that the relationship for the water curing case is not consistent. This might be attributed to the rehydration and crack-healing process during water-curing. The present study can form a basis for the future application of the stress wave velocity technique for assessment of the engineering properties of the fire-damaged slag concrete.