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.

The development of lightweight concretes has made a contribution to advances in structural design. It would be useful to further improve the mechanical properties of lightweight concrete formulations whilst enhancing their resistance to fire degradation and reduced thermal conductivity. Improving the sustainability of any new proposed lightweight concrete formulation is desirable, for example by the inclusion of waste stream components into the formulation.This thesis describes an investigation of the mechanical, thermal and fire resistance properties of a new type of expanded clay lightweight concrete formulation in which varying quantities of sand are replaced by crushed glass aggregate, in conjunction with the addition of metakaolin (which may be available as a waste component from the manufacture of paper) as a partial replacement for the cement. The investigation involved short and long-term laboratory testing of a range of mechanical and thermal properties of individual concrete formulations and small scale structural elements consisting of masonry blocks made from these formulations (so called wallettes). An extensive programme of Finite Element Analysis using Abaqus was also performed.The results obtained show that it is possible to produce a structural expanded clay lightweight concrete that possesses good thermal properties by incorporating of ground glass and metakaolin. Compressive and splitting tensile strengths, as well as the modulus of elasticity, increased with an increase in the metakaolin content, while concrete density decreased. Reductions in thermal conductivity and improvements in fire resistance criteria were also observed in comparison with conventional lightweight concrete mixtures. For example, measured thermal conductivity values ranged from 0.092 W/m.K to 0.177 W/m.K, and the insulation criterion (an indicator of resistance to fire) reached up to 110 minutes for a concrete member with a thickness of 29 mm. The highest resistance to the effects of high temperatures was observed for concrete mixes containing either 15% or 30% recycled glass with 10% metakaolin.The maximum axial loads at failure were 474 kN and 558 kN for reference and modified wallettes respectively, implying corresponding bearing capacities of 7.1 MPa and 8.3 MPa. The critical path of the failure mode was similar for all of the wallettes tested and normally began underneath the load point, then passed through the concrete blocks and head joint to reach the toe of the wallette. The masonry wallettes formulated using reference lightweight concrete blocks exhibited failure due to explosive spalling at 400 oC with no applied mechanical load, whereas the second type of masonry wallettes (the modified wallettes) did not show such behaviour.The results of Finite Element Analysis showed that the coefficient of thermal convection had the most influence upon the insulation criterion. From a structural perspective, the key parameters were the value of penalty stiffness and imperfections in wallette construction. In general, a close agreement between the measured and simulated results was observed for both the thermal and structural finite element models at ambient and high temperatures.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-19T15:13:28Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese completa - com FICHA CATALOGRÁFICA - 13-11-15.docx.pdf: 12354706 bytes, checksum: ca0e4da17bca37b3d26461335b9c9552 (MD5) / Made available in DSpace on 2016-04-19T15:13:29Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese completa - com FICHA CATALOGRÁFICA - 13-11-15.docx.pdf: 12354706 bytes, checksum: ca0e4da17bca37b3d26461335b9c9552 (MD5) Previous issue date: 2015-11-15 / Estima-se a existência, desde a década de 1960, de milhares de edifícios de alvenarias de vedação com função estrutural na Região Metropolitana do Recife (RMR). Esses prédios tipo “caixão” foram concebidos, em sua maioria, com blocos cerâmicos com furos na horizontal e possuem até quatro pavimentos. Verifica-se que essas paredes não apresentam requisitos técnicos e desempenho necessários para serem considerados estruturais, de tal forma que o cálculo da resistência à compressão mostra insuficiência na capacidade de suporte, por conseguinte, não atendem a critérios normativos. Portanto, observam-se elevados níveis de patologias e envelhecimento precoce, onde a relação entre o número de acidentes e o número de edificações existentes apresenta probabilidade de falha de aproximadamente 1:500, bem acima do nível aceitável quando envolve a segurança de vidas humanas que é de 1:10.000. Ocorreram 12 desabamentos desses prédios nos últimos 30 anos na RMR, causando 12 mortes. Assim, torna-se importante apresentar um modelo de reforço para estas edificações, especialmente quando se considera que nesses prédios residem cerca de 250.000 pessoas. Este trabalho tem por objetivo avaliar o reforço com argamassa armada e adição de metacaulim na resistência compressiva, ductilidade e durabilidade. Moldaram-se prismas de amostras sem e com reforço sobre substrato sem revestimento e revestido. O reforço foi constituído por capa de argamassa com tela de aço nas duas faces interligadas por conectores de aço e adição de 15% de metacaulim, adicionado por substituição de parte de cimento e adição simples, com traços em volume: 1:1:6:1,5 e 1:0,5:4,5:1,5 (cimento, cal, areia, relação água/cimento). Concluiu-se diante dos ensaios que o reforço proposto contribui substancialmente na resistência à compressão (considerando o fator redutor devido efeito de flambagem) e na forma de ruptura, fornecendo ductilidade (deformação plástica e tenacidade), bem como a metacaulim contribui para a durabilidade, visto em ensaios próprios específicos (resistência mecânica, módulo de elasticidade, velocidade de propagação da onda ultrassônica, absorção por imersão e ensaios acelerados de carbonatação e cloretos). / In Recife Metropolitan Region (RMR), there are thousands of buildings made of non-structural masonry dating from the 1960s, however performing as structural masonry. These four-floor buildings best known as “caixão” were mostly conceived with ceramic bricks horizontally perforated. This kind of masonry does not supply technical requirements and does not perform appropriately to be considered structural. It does not fulfill normative criteria because structural calculus shows that its resistance to compression does not suffice. This consequently leads to high levels of pathologies and premature aging of buildings. The relationship between the quantity of “caixão” buildings in RMR and the number of accidents they are involved in indicates that the probability of failure is about 1:500. This rate is much above the acceptable standard of 1:10.000 concerning human lives safety. Over the past thirty years, 12 “caixão” buildings tumbled down in RMR, causing 12 deaths. It is, thus, relevant to develop a solution for reinforcing these buildings, where approximately 250.000 people live. This study aims to evaluate the use of reinforced mortar and metakaolin addition for reinforcing masonry in order to increase its resistance to compression, ductility and durability. In this research, we shaped sample prisms with and without reinforcement on both mortar and non-mortar substratum. The reinforcement consisted of a layer of mortar with a steel lattice on both faces connected by steel connectors as well as addition of 15% of metakaolin, partly replaced with cement by pure addition, following the volume proportions of 1:1:6:1,5 and 1:0,5:4,5:1,5 (cement, lime, sand, water/cement relation). Conclusively, our proposal substantially increased the masonry resistance to compression, considering the reduction factor due to the buckling effect, providing it with ductility, that is, plastic deformation and tenacity. Additionally, we found that the metakaolin contributes to masonry durability by doing specific experiments of mechanical resistance, elasticity modulus, ultrasound, and absorption by immersion as well as accelerated experiments of carbonation and chlorides.

Made available in DSpace on 2017-06-01T17:57:37Z (GMT). No. of bitstreams: 1 marcelo_lima_silva_textual.pdf: 1991447 bytes, checksum: b4453b4c4677952d7d84a16e3945a5ed (MD5) Previous issue date: 2016-04-08 / The risk collapse of Building type box is alarming. Most of these buildings have some potential risk. About 10% of the population of Pernambuco lives in this type building. The Military Fire Department of Pernambuco (CBMPE) attended in 2012 in RMR 314 occurrences in residential building and in 2013 had 325 residential fires. In the city of Recife in 2013 were 198 occurrences of residential fire being 36 in multifamily buildings, the same occupation of the buildings type box. In this work is presented a case study of a fire in an apartment, where its effects on masonry were observed, and it is verified that these effects could lead to collapse in a Resistant Masonry building, because in this type of building the walls is supporting masonry structure. Such estimates were about the strength in compression of the walls considering reductions in resistance resulting from fire damage. Studies show that the resistant masonry buildings to have their guaranteed stability depend on the participation of the coating on compressive strength. The rules for the structural masonry recommend that should not be considered the contribution of the coating in its strength in compression. However, without the contribution of the coating the structure was numerically outside safe limits. The effects of fire may result in the destruction of the plaster on one side of the wall, and around one third of the ceramic block, which should represent the ruin of the building if it had occurred on the ground floor. / O risco de colapso em estruturas de prédio do tipo caixão é alarmante. A maioria desses prédios tem algum risco potencial. Cerca de 10% da população de Pernambuco habitam nesse tipo de edificação. O Corpo de Bombeiros Militar de Pernambuco (CBMPE) atendeu no ano de 2012 na RMR a 314 ocorrências em residências e em 2013 teve 325 incêndios residenciais. Na cidade de Recife, em 2013, foram 198 ocorrências de incêndio residenciais sendo 36 em edificações multifamiliares, mesmo tipo de ocupação dos prédios tipo caixão. Neste trabalho, apresenta-se um estudo de caso de um incêndio em um apartamento, onde foram observados seus efeitos sobre a alvenaria e verificou-se se esses efeitos poderiam provocar o colapso em um edifício de Alvenaria Resistente, uma vez que nesse tipo de edificação as paredes têm função estrutural. Essas estimativas foram acerca da resistência à compressão nas paredes considerando as reduções de resistência decorrentes dos danos provocados pelo incêndio. Estudos demonstram que os prédios em alvenaria resistente para terem a sua estabilidade assegurada dependem da participação do revestimento na resistência à compressão. As normas relativas à alvenaria estrutural recomendam que não deva ser considerada a contribuição do revestimento. No entanto, sem a contribuição do revestimento, a estrutura estaria numericamente fora dos limites de segurança. Efeitos decorrentes do incêndio poderão ocasionar destruição do revestimento e um terço do bloco cerâmico nas faces expostas ao incêndio, o que deve representar a ruína do edifício se ocorrido no pavimento térreo.

A norma que prescreve o cálculo de alvenaria estrutural de blocos vazados de concreto, NBR 10837:1989, encontra-se em fase de revisão, sendo que a principal alteração é a introdução do método dos estados limites no dimensionamento e na verificação dos elementos de alvenaria. Neste trabalho, estudam-se duas normas para alvenaria, a NBR 10837:1989 e EC 6:1996, e o texto proposto para revisão da NBR 10837. A escolha do EC 6:1996 se deu pela sua importância em relação à comunidade européia e porque muitas das prescrições contidas nessa norma foram adaptadas para o texto de revisão da NBR 10837. Quando necessárias, são realizadas comparações entre as duas normas e o texto de revisão, com o intuito de auxiliar no entendimento das implicações que a mudança de abordagem causará. Vários exemplos que simulam situações típicas de projeto, como compressão simples, flexão e cisalhamento, são apresentados. Com a variação dos diversos parâmetros envolvidos no dimensionamento dos elementos de alvenaria, é possível a elaboração de gráficos e ábacos. Desta forma consegue-se englobar uma grande variedade de situações, e a comparação entre as respostas obtidas com cada uma das normas e com o texto de revisão torna-se bem mais simples e precisa. Pretende-se, com este trabalho, contribuir para a introdução do método dos estados limites na norma de cálculo de alvenaria estrutural, bem como avaliar as mais importantes adaptações propostas. / The code that regulates the design of concrete blockwork structural masonry, NBR 10837:1989, is under revision phase. The main change is the introduction of limit state method for the design and verification of masonry elements. In this work, two masonry codes (NBR 10837:1989 and EC 6:1996) and a proposed revised text for the NBR 10837 are studied. The choice for EC 6:1996 is justified by its importance to european community and because many clauses of the revised text are adapted from that code. When necessary, comparisons between the two codes and revised text are carried out, to help the understanding of the changes implications. Some examples, that simulate typical design situation, such as axial compression, bending and shear are presented. A parametric study on the masonry elements design is carried out, allowing for the elaboration of graphs and abacus. Thus, various situations are explored, showing different results corresponding to each one of the codes and the revision text, in order to clarify the comparisons. The general aim of this work is help the introduction of the limit state method in the masonry code, and to evaluate the most important changes in the proposed revised text of the brazilian code.

In this study, parameters related to material properties, geometry, and external stimuli were examined individually to determine their influence on multi-story, partially grouted, perforated (openings), masonry shear walls using a finite element software FormWorks. The parameters studied were: the strength of grouted masonry prisms f'm,grouted; the strength of un-grouted (hollow) masonry prisms f'm,ungrouted; the ratio of mortar shear strength to masonry compressive strength; vertical and horizontal reinforcement ratios in terms of size and spacing of reinforcement; axial load; aspect ratio; and openings that were vertically and horizontally altered. To perform this study, finite element models were validated against the response of three experimental walls of two unique types that were built ½ scale and tested in a lab. The validated finite element models were designated as "base models" which accurately predicted the maximum strength of each wall within a tolerance of 5.9%, 3.3%, and 1.8%. Following validation, each parameter in question was varied individually to identify and quantify the sensitivity of the parameter and to observe the changes in shear capacity and deflection for this unique configuration of masonry shear walls. To capture the impact of these parameters, 38 different shear wall models were built and tested. The results were compared against the Masonry Standards Joint Committee (MSJC) (2013) code predictions using the applicable shear strength equations. Results of this study are specific to cantilever type masonry shear walls with large aspect ratios and openings in every story. Shear wall capacity was considered sensitive to the following parameters: compressive strength of grouted masonry; compressive strength of un-grouted masonry; joint strength ratio; vertical reinforcement ratio; axial stress; aspect ratio; and opening width. Shear wall capacity was considered not sensitive to the following parameters: horizontal reinforcement ratio; vertical reinforcement spacing; and horizontal reinforcement spacing. The sensitivity of shear wall capacity to opening height was determined inconclusive. The sensitivities were determined by fitting trend lines to the results of shear capacity vs. each parameter individually. Each MSJC (2013) code prediction un-conservatively over-predicted the shear wall capacity except one wall configuration that had a joint strength ratio of 0.045.

In this study, parameters related to material properties, geometry, and external stimuli were examined individually to determine their influence on multi-story, partially grouted, perforated (openings), masonry shear walls using a finite element software FormWorks. The parameters studied were: the strength of grouted masonry prisms f<&trade>m,grouted; the strength of un-grouted (hollow) masonry prisms f<&trade>m,ungrouted; the ratio of mortar shear strength to masonry compressive strength; vertical and horizontal reinforcement ratios in terms of size and spacing of reinforcement; axial load; aspect ratio; and openings that were vertically and horizontally altered. To perform this study, finite element models were validated against the response of three experimental walls of two unique types that were built ½ scale and tested in a lab. The validated finite element models were designated as œbase models which accurately predicted the maximum strength of each wall within a tolerance of 5.9%, 3.3%, and 1.8%. Following validation, each parameter in question was varied individually to identify and quantify the sensitivity of the parameter and to observe the changes in shear capacity and deflection for this unique configuration of masonry shear walls. To capture the impact of these parameters, 38 different shear wall models were built and tested. The results were compared against the Masonry Standards Joint Committee (MSJC) (2013) code predictions using the applicable shear strength equations. Results of this study are specific to cantilever type masonry shear walls with large aspect ratios and openings in every story. Shear wall capacity was considered sensitive to the following parameters: compressive strength of grouted masonry; compressive strength of un-grouted masonry; joint strength ratio; vertical reinforcement ratio; axial stress; aspect ratio; and opening width. Shear wall capacity was considered not sensitive to the following parameters: horizontal reinforcement ratio; vertical reinforcement spacing; and horizontal reinforcement spacing. The sensitivity of shear wall capacity to opening height was determined inconclusive. The sensitivities were determined by fitting trend lines to the results of shear capacity vs. each parameter individually. Each MSJC (2013) code prediction un-conservatively over-predicted the shear wall capacity except one wall configuration that had a joint strength ratio of 0.045.

This master’s thesis deals with preparation of foam glass and explores the possibilies of utilization of this material as an inorganic thermal insulating filler of fired hollow bricks. Foam glass was prepared via powder sintering method from waste packaging glass, using limestone and graphite as foaming agents. After inital analysis of raw materials, the effect of mixture composition and different processing parameters on bulk density, pore size and morphology of foam glass was investigated. Last but not least, different ways of manufacturing thermal insulating bricks, by preparation of foam glass directly in the cavities of fired hollow bricks, were tested.

This thesis presents results from testing of interlocking compressed earth block (CEB) masonry shear walls. CEBs are low strength earth masonry units sometimes stabilized with cement or lime. The interlocking compressed earth blocks (ICEBs) used in this experiment are dry stacked interlocking hollow units, which can be reinforced and grouted after they are laid. Although significant research has been undertaken to optimize the material properties of CEBs, little has been done to investigate the performance of structural systems currently being built using this technology. Test results are reported for three 1800 mm x 1800 mm wall specimens constructed with cement stabilized ICEBs and subjected to cyclic in-plane lateral loading. Wall specifications were varied to identify the shear performance of partial and fully grouted walls, and to observe the performance of a flexure dominated wall panel. It was determined that the shear strength of fully grouted walls is significantly higher than that of partially grouted walls and calculation of capacity based on current ACI 530-08 masonry provisions significantly overestimates the shear strength of ICEB wall panels. Based on the observed performance, recommendations are made for limiting the calculated nominal shear strength in design. Results also indicate that calculations based on simple bending theory conservatively predict the flexural strength of a fully grouted ICEB wall. Discussion of ICEB material properties and recommendations for design and construction procedures are included.

This thesis deals with the monitoring of buildings disorders caused by surrounding con-struction activity. The first section describes the methods of monitoring failures, from the detailed inspection to the result evaluation, there is also given an overview of measuring instruments. The second part describes the methodology of passports implementation and contains an example of the object repassport that was violated by tunneling. There is a comparison of passport and repassport. The third largest section describes a practical ex-ample of monitoring object cracks around which the building activity took place. There is a documentation of failures, a description of the measuring spots choise, installation of the bases, monitoring, processing of results and conclusion.