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Following the evolution of a damage avoidance design (DAD) frame system, with rocking beam-column joints, at the University of Canterbury, analytical studies are carried out to evaluate the performance of proposed structures, and verify the proposed design methodology. A probabilistic seismic risk assessment methodology is proposed, from which the expected annualised financial loss (EAL) of a structure can be calculated. EAL provides a consistent basis for comparison of DAD frame systems with state-of-practice ductile monolithic construction. Such comparison illustrates the superior performance of DAD frame systems. The proposed probabilistic seismic assessment methodology requires the response of the structure to be evaluated over a range of seismic intensities. This can be achieved by carrying out an incremental dynamic analysis, explicitly considering seismic randomness and uncertainty; or from a pushover analysis, and assuming an appropriate value of the dispersion. By combining this information with the seismic hazard, probabilistic response curves can be derived, which when combined with information about damage states for the particular structure, can be transformed into 'resilience curves'. Integration of information regarding the financial loss occurring due to each of the damage states, results in an estimate of EAL.

The seismic design of buildings is usually performed using one-way analysis for each of main axes independently. However, seismic events have fairly random behaviour and impose bidirectional solicitations on structures. In this work, the study of the response in structures subjects to earthquake loads with irregularity of l-shaped plan and soft story is carried out. For this, the linear time-story analysis (LTHA) of these has been carried out imposing seismic solicitations in two orthogonal directions. Thus, the structural response with incidence angle variations of 10 is obtained and compared with the response derived from the unidirectional analysis. Variations of up to 50% and 72% are obtained for model structures with l-shaped plan and soft story respectively.

Reinforced concrete structures designed in pre-1970s are vulnerable under earthquakes due to lack of seismic detailing to provide adequate ductility. Typical deficiencies of pre-1970s reinforced concrete structures are (a) use of plain bars as longitudinal reinforcement, (b) inadequate anchorage of beam longitudinal reinforcement in the column (particularly exterior column), (c) lack of joint transverse reinforcement if any, (d) lapped splices located just above joint, and (e) low concrete strength. Furthermore, the use of infill walls is a controversial issue because it can help to provide additional stiffness to the structure on the positive side and on the negative side it can increase the possibility of soft-storey mechanisms if it is distributed irregularly. Experimental research to investigate the possible seismic behaviour of pre-1970s reinforced concrete structures have been carried out in the past. However, there is still an absence of experimental tests on the 3-D response of existing beam-column joints under bi-directional cyclic loading, such as corner joints. As part of the research work herein presented, a series of experimental tests on beam-column subassemblies with typical detailing of pre-1970s buildings has been carried out to investigate the behaviour of existing reinforced concrete structures. Six two-third scale plane frame exterior beam-column joint subassemblies were constructed and tested under quasi-static cyclic loading in the Structural Laboratory of the University of Canterbury. The reinforcement detailing and beam dimension were varied to investigate their effect on the seismic behaviour. Four specimens were conventional deep beam-column joint, with two of them using deformed longitudinal bars and beam bars bent in to the joint and the two others using plain round longitudinal bars and beam bars with end hooks. The other two specimens were shallow beam-column joint, one with deformed longitudinal bars and beam bars bent in to the joint, the other with plain round longitudinal bars and beam bars with end hooks. All units had one transverse reinforcement in the joint. The results of the experimental tests indicated that conventional exterior beam-column joint with typical detailing of pre-1970s building would experience serious diagonal tension cracking in the joint panel under earthquake. The use of plain round bars with end hooks for beam longitudinal reinforcement results in more severe damage in the joint core when compared to the use of deformed bars for beam longitudinal reinforcement bent in to the joint, due to the combination of bar slips and concrete crushing. One interesting outcome is that the use of shallow beam in the exterior beam-column joint could avoid the joint cracking due to the beam size although the strength provided lower when compared with the use of deep beam with equal moment capacity. Therefore, taking into account the low strength and stiffness, shallow beam can be reintroduced as an alternative solution in design process. In addition, the presence of single transverse reinforcement in the joint core can provide additional confinement after the first crack occurred, thus delaying the strength degradation of the structure. Three two-third scale space frame corner beam-column joint subassemblies were also constructed to investigate the biaxial loading effect. Two specimens were deep-deep beam-corner column joint specimens and the other one was deep-shallow beam-corner column joint specimen. One deep-deep beam-corner column joint specimen was not using any transverse reinforcement in the joint core while the two other specimens were using one transverse reinforcement in the joint core. Plain round longitudinal bars were used for all units with hook anchorage for the beam bars. Results from the tests confirmed the evidences from earthquake damage observations with the exterior 3-D (corner) beam-column joint subjected to biaxial loading would have less strength and suffer higher damage in the joint area under earthquake. Furthermore, the joint shear relation in the two directions is calibrated from the results to provide better analysis. An analytical model was used to simulate the seismic behaviour of the joints with the help of Ruaumoko software. Alternative strength degradation curves corresponding to different reinforcement detailing of beam-column joint unit were proposed based on the test results.

Neste trabalho são apresentadas duas importantes áreas de pesquisa voltadas para problemas de otimização: a Programação Matemática e, especialmente, os Algoritmos Genéticos. São classificados grande parte dos métodos clássicos da Programação Matemática, com uma breve apresentação das suas classes de subproblemas, bem como detalhes de alguns métodos. O desenvolvimento da ciência que explica a evolução das espécies é descrito, como uma ponte para a compreensão da técnica dos Algoritmos Genéticos. Apresentam-se as diferenças básicas entre os Métodos Clássicos e os Algoritmos Genéticos, com posterior análise das vantagens e desvantagens entre estas duas classes de ferramentas de otimização. São apresentados os principais parâmetros de influência no funcionamento de um Algoritmo Genético e algumas recomendações quanto às suas configurações. A essência desse trabalho se constitui em alguns exemplos de otimização de estruturas de concreto armado, como o de um trecho de Pilar dimensionado à Flexão Composta Obliqua e um Pórtico Plano de Concreto Armado de Cinco Pavimentos. Finalizando, conclui-se pela tendência promissora dos Algoritmos Genéticos para os próximos anos, o que tornará esta técnica uma das mais importantes e empregadas na resolução de uma vasta gama de aplicações. / This work addresses two important issues of Optimization: Mathematical Programming and Genetic Algorithms. First, classes of optimization problems, that can be handled by the classical methods of Mathematical Programming, are briefly presented. After that, the techniques of Genetic Algorithms are displayed in detail. Such methods are inspired by the laws that rules the evolution of the species. The basic differences between the Mathematical Programming and Genetic Algorithms are deeply discussed. The main parameters that control Genetic Algorithms are described and some recommendations about their values are made.The work is concluded y some optimization examples of reinforced concrete structures, as a column under combined axial load and bi-axial bending and a five floor reinforced concrete plane frame.

Este trabalho discute caminhos para tornar o projeto de detalhamento da armadura um indutor da melhoria da produtividade da mão-de-obra no serviço de armação. Uma revisão bibliográfica inicial precede a apresentação de estudos de campo, que foram realizados para se entender como a produtividade em armação varia. Tal entendimento (expresso na forma de faixas de variação da produtividade e apresentação dos fatores influenciadores) deu apoio a entrevistas com projetistas, visando levantar suas opiniões sobre as alterações no projeto, levando à melhoria da produtividade, que seriam mais viáveis de serem adotadas. Em paralelo, estudaram-se as diferentes formas de apresentação dos projetos de detalhamento da armadura e, uma vez descritas estas possibilidades, coletaram-se as opiniões de gestores da produção sobre as formas de representação mais convenientes. Todos estes conhecimentos, de base teórica e empírica, servem de subsídio para a tomada de decisões sobre diretrizes a serem seguidas na futura elaboração de projetos de detalhamento da armadura, o que é bastante desejável no sentido de se aumentar a competitividade das empresas de construção de edifícios. / This thesis presents directions to make the steel reinforcement design a tool to improve rebar labor productivity. Bibliography review served as basis to go through a site study that allowed understanding rebar labor productivity variation. Such an information, expressed in terms of a labor productivity unit rate range associated to the influencing factors presentation, supported designers interviews where they stated the ideas they are willing to use in their designs to improve labor productivity. The thesis also discusses different approaches to be used in order to represent the product being defined in the design. In this case, production managers were listened to, aiming to understand the ones they prefer. The whole knowledge here described, coming from theory or reality evaluation, can help managers in taking decisions in relation to the steel reinforcement design directions to be followed. This can be very helpful to make construction companies more competitive.

Submitted by Cátia Araújo (catia.araujo@unipampa.edu.br) on 2017-01-25T11:42:49Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Corrosao acelerada por imersao modificada (ensaio CAIM) de estruturas de concreto armado contendo cinza da casaca de arroz e agua da mandioca brava.pdf: 4431848 bytes, checksum: a3ec1c3261aeadc9e8ab4cda79be3199 (MD5) / Approved for entry into archive by Cátia Araújo (catia.araujo@unipampa.edu.br) on 2017-01-25T11:44:41Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Corrosao acelerada por imersao modificada (ensaio CAIM) de estruturas de concreto armado contendo cinza da casaca de arroz e agua da mandioca brava.pdf: 4431848 bytes, checksum: a3ec1c3261aeadc9e8ab4cda79be3199 (MD5) / Made available in DSpace on 2017-01-25T11:44:41Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Corrosao acelerada por imersao modificada (ensaio CAIM) de estruturas de concreto armado contendo cinza da casaca de arroz e agua da mandioca brava.pdf: 4431848 bytes, checksum: a3ec1c3261aeadc9e8ab4cda79be3199 (MD5) Previous issue date: 2013-12-06 / A corrosão de armaduras e uma das manifestações patológicas mais comuns encontradas em estruturas de concreto armado, consistindo em um processo eletroquímico onde a agua presente no concreto atua como eletrólito. Neste sentido através do ensaios de corrosão acelerados (ensaio CAIM) comparou-se a resistência a corrosão no concreto armado de diferentes traços na presença e ausência de insumos agrícolas como a cinza da casca de arroz e agua extraída da mandioca brava. O objetivo principal do presente trabalho foi seleciona qual (quais) o (s) traços (s) com similaridade de resistência frente ao processo de corrosão e teor de argamassa apresentaram maior resistência frente ao processo de corrosão em meio contendo íons cloretos (solução que simula agua do mar - 35g/L NaCl), aplicando-se voltagens de 15, 30 e 70V durante 8, 24 e 48h. A cinza de casca de arroz e a agua extraída da mandioca brava foram caracterizadas pelas técnicas de analise de espectroscopia de infravermelho e de difração de raios-X. Os grupos funcionais silanol e carboxila foram detectados nestes subprodutos agrícolas e relacionados a um mecanismo proposto de inibição contra a corrosão na armadura conforme dados do ensaio CAIM. Analises de microscopia eletrônica de varredura e energia dispersiva de raios-X colaboraram para elucidar o mecanismo proposto. Enquanto que as analises de perda de massa e quantificação de cloretos no concreto apos ensaio CAIM através do método de Mohr auxiliaram na validação dos resultados do ensaio. / The corrosion in armatures is one of the most common pathologies found in structures of concrete, consisting in an electrochemical process, where the water in the concrete acts as an electrolyte. In this way, through the assays of accelerated corrosion (CAIM Tests), the resistance to corrosion in concrete of different mixtures was compared with the presence and absence of agricultural input so as rice husk and water from mandioca brava. The main objective of this work is to select mixture with similarity in resistance to compression and group content present the biggest resistance against the corrosion process amid containing chloride ions (solution simulating seawater – 35g/L NaCI), applying voltages of 15, 30 and 70V during 8, 24 and 48h. The cinder of rice husk and the water extracted from mandioca brava were characterized by the infrared spectroscopy analysis technics and by X-ray diffraction. The functional groups of silanol and carboxyl were detected in these agricultural byproducts and related to a proposed inhibition mechanism against the corrosion in armatures seen in CAIM data test. Electronic scanning microscopic analysis and dispersive X-ray energy collaborated to elucidated the proposed mechanism. While the studies in weight loss and chloride quantification in concrete after the CAIM test through the Mohr method helped in the validation of the assay results.

Neste trabalho são apresentadas duas importantes áreas de pesquisa voltadas para problemas de otimização: a Programação Matemática e, especialmente, os Algoritmos Genéticos. São classificados grande parte dos métodos clássicos da Programação Matemática, com uma breve apresentação das suas classes de subproblemas, bem como detalhes de alguns métodos. O desenvolvimento da ciência que explica a evolução das espécies é descrito, como uma ponte para a compreensão da técnica dos Algoritmos Genéticos. Apresentam-se as diferenças básicas entre os Métodos Clássicos e os Algoritmos Genéticos, com posterior análise das vantagens e desvantagens entre estas duas classes de ferramentas de otimização. São apresentados os principais parâmetros de influência no funcionamento de um Algoritmo Genético e algumas recomendações quanto às suas configurações. A essência desse trabalho se constitui em alguns exemplos de otimização de estruturas de concreto armado, como o de um trecho de Pilar dimensionado à Flexão Composta Obliqua e um Pórtico Plano de Concreto Armado de Cinco Pavimentos. Finalizando, conclui-se pela tendência promissora dos Algoritmos Genéticos para os próximos anos, o que tornará esta técnica uma das mais importantes e empregadas na resolução de uma vasta gama de aplicações. / This work addresses two important issues of Optimization: Mathematical Programming and Genetic Algorithms. First, classes of optimization problems, that can be handled by the classical methods of Mathematical Programming, are briefly presented. After that, the techniques of Genetic Algorithms are displayed in detail. Such methods are inspired by the laws that rules the evolution of the species. The basic differences between the Mathematical Programming and Genetic Algorithms are deeply discussed. The main parameters that control Genetic Algorithms are described and some recommendations about their values are made.The work is concluded y some optimization examples of reinforced concrete structures, as a column under combined axial load and bi-axial bending and a five floor reinforced concrete plane frame.

Este trabalho discute caminhos para tornar o projeto de detalhamento da armadura um indutor da melhoria da produtividade da mão-de-obra no serviço de armação. Uma revisão bibliográfica inicial precede a apresentação de estudos de campo, que foram realizados para se entender como a produtividade em armação varia. Tal entendimento (expresso na forma de faixas de variação da produtividade e apresentação dos fatores influenciadores) deu apoio a entrevistas com projetistas, visando levantar suas opiniões sobre as alterações no projeto, levando à melhoria da produtividade, que seriam mais viáveis de serem adotadas. Em paralelo, estudaram-se as diferentes formas de apresentação dos projetos de detalhamento da armadura e, uma vez descritas estas possibilidades, coletaram-se as opiniões de gestores da produção sobre as formas de representação mais convenientes. Todos estes conhecimentos, de base teórica e empírica, servem de subsídio para a tomada de decisões sobre diretrizes a serem seguidas na futura elaboração de projetos de detalhamento da armadura, o que é bastante desejável no sentido de se aumentar a competitividade das empresas de construção de edifícios. / This thesis presents directions to make the steel reinforcement design a tool to improve rebar labor productivity. Bibliography review served as basis to go through a site study that allowed understanding rebar labor productivity variation. Such an information, expressed in terms of a labor productivity unit rate range associated to the influencing factors presentation, supported designers interviews where they stated the ideas they are willing to use in their designs to improve labor productivity. The thesis also discusses different approaches to be used in order to represent the product being defined in the design. In this case, production managers were listened to, aiming to understand the ones they prefer. The whole knowledge here described, coming from theory or reality evaluation, can help managers in taking decisions in relation to the steel reinforcement design directions to be followed. This can be very helpful to make construction companies more competitive.

No description available.