[pt] A indústria de geração elétrica de fonte nuclear baseia-se em princípios de segurança e, nos critérios de projeto, considera-se a hipótese de terremoto. Os sistemas necessários à segurança são projetados para resistir e manter a operabilidade durante e após eventos sísmicos postulados. Propõe-se um roteiro para a produção de espectros de resposta sísmica para projeto de sistemas secundários, SS, incluindo a influência do acoplamento e em base probabilística. O roteiro utiliza a ferramenta SASSI, pode ser utilizado em situações gerais de cálculo e fornece um conjunto de programas para considerar modelos tridimensionais e suas respostas para uma excitação genérica em 3 direções ortogonais; representar os efeitos de acoplamento entre o SS e o sistema principal, SP; incluir a influência dos deslocamentos relativos entre os nós de apoio do sistema secundário no sistema principal; utilizar os fatores de transposição entre espectros elásticos e inelásticos; permitir a análise probabilística e a obtenção de Espectros de Resposta Uniformemente Prováveis, acoplados ou não; incluir interfaces para a utilização de seus resultados com outros programas de utilização geral, como o MS-EXCEL. O elevado grau de automatização permite a produção de espectros de resposta com refinamentos de modelagem, alcançando uma análise mais realista, sem a necessidade de esforços adicionais aos já requeridos pela metodologia convencional. A metodologia proposta enquadra-se no encaminhamento para o contexto atual de análise sísmica de instalações nucleares, com a utilização de espectros de resposta de projeto de ameaça uniforme, específico para o sítio da instalação, e o projeto sísmico de risco consistente. / [en] The electric power reactor industry is based on rigid safety principles. The design criteria include seismic scenario. All safety related systems are designed to resist and to keep the operability during and after a postulated earthquake. It is suggested a procedure for the generation of in-structure seismic response spectra for secondary system design. A probabilistic approach is used and coupling effects between primary and secondary systems are taken into account. The proposed script uses SASSI system and can be used in general situations. A set of computer programs is developed to consider three-dimensional models and their responses for a generic base excitation, acting in 3 orthogonal directions; represent the coupling effect between primary and secondary systems, include the influence, on the response spectra, of the secondary system supports relative displacements; include approximated factors for transposition of elastic into inelastic response spectra; produce Uniformly Probable Response Spectra, including or not coupling effects; consider interfaces with other general programs, as the MS-EXCEL, for pos-processing purpose. The degree of automation, allows the production of response spectra including modeling refinements, reaching a more realistic analysis, without additional efforts beyond those already required by the conventional methodology. The proposed methodology is in the way of a site specific uniform hazard design response spectra, and of a consistent-risk seismic design.

Apesar de fortes eventos sísmicos serem raros no Brasil, engenheiros estruturais brasileiros são frequentemente envolvidos em tal análise para os países latino-americanos vizinhos. Informações sobre históricos de aceleração sísmica, de natureza aleatória, não estão em geral disponíveis, devido, em parte, à falta de registros. Para contornar tal situação, os códigos de construção indicam o uso de acelerogramas artificiais, mas não fornecem metodologia para sua obtenção. A informação normalizada é o chamado espectro de resposta elástico, que fornece a aceleração de resposta máxima para um sistema linear de um grau de liberdade. Muitas pesquisas estão sendo desenvolvidas a fim de gerar acelerogramas artificiais compatíveis com os espectros de norma. Assim, neste trabalho se apresenta uma proposta para a geração de acelerograma artificial compatível com espectro de resposta regulamentar. Para exemplo de aplicação, é gerado um acelerograma artificial compatível com a Norma Brasileira NBR 15421: 2006 e aplicado à base de um edifício shear building de dez pavimentos e através de integração numérica por diferenças finitas passo-a-passo no domínio do tempo é calculado o deslocamento do último pavimento deste edifício. De forma semelhante, é gerado um acelerograma artificial compatível com a Norma Venezuelana COVENIN 1756: 2001 e aplicado à base de um reservatório d\'água sobre quatro pilares e estudado o seu comportamento elastoplástico perfeito. / Although strong seismic events are rare in Brazil, Brazilian structural engineers are often involved in such an analysis for neighboring Latin American countries. Information on seismic acceleration histories of a random nature is not generally available, due in part to the lack of records. To circumvent such a situation, building codes indicate the use of artificial accelerograms, but do not provide a methodology for obtaining them. The normalized information is the so-called elastic response spectrum, which provides the maximum response acceleration for a linear system of a degree of freedom. Many researches are being developed in order to generate artificial accelerograms compatible with the norm spectra. Thus, this paper presents a proposal for the generation of an artificial accelerogram compatible with a regulatory response spectrum. For an application example, an artificial accelerogram compatible with the Brazilian Standard NBR 15421: 2006 is generated and applied to the base of a ten-story shear building and through numerical integration by finite differences step-by-step in the time domain is calculated the displacement of the last floor of this building. Similarly, an artificial accelerogram is generated that is compatible with the Venezuelan Standard COVENIN 1756: 2001 and applied on the basis of a water reservoir on four pillars and studied its perfect elastoplastic behavior.

The emphasis on seismic design and assessment of reinforced concrete (RC) frame structure has shifted from force-based to performance-based design and assessment to accommodate strength and ductility for required performance of building. RC frame structure may suffer different levels of damage under seismic-induced ground motions, with potentials for formation of hinges in structural elements, depending on the level of stringency in design. Thus it is required to monitor the seismic behaviour and performance of buildings, which depend on the structural system, year of construction and the level of irregularities in the structural system. It is the objective of the current research project to assess seismic performance of RC frame buildings in Canada, while developing fragility curves as analytical tools for such assessment. This was done through dynamic inelastic analysis by modelling selected building structures and using PERFORM-3D as analysis software, while employing incremental dynamic analysis to generate performance data under incrementally increasing seismic intensity of selected earthquake records. The results lead to probabilistic tools to assess the performance of buildings designed following the National Building Code of Canada in different years of construction with and without irregularities. The research consists of three phases; i) regular buildings designed after 1975, ii) regular buildings designed prior to 1975, and iii) irregular buildings designed prior to 1975. The latter two phases address older buildings prior to the development of modern seismic building codes. All three phases were carried out by selecting and designing buildings in Ottawa, representing the seismic region in eastern Canada, as well as buildings in Vancouver, representing the seismic region in western Canada. Buildings had three heights (2; 5; and 10-stories) to cover a wide range of building periods encountered in practice. The resulting fragility curves indicated that the older buildings showed higher probabilities of exceeding life safety and/or collapse prevention performance levels. Newer buildings showed higher probabilities of exceeding target performance levels in western Canada than those located in the east.

L'analyse sismique des structures de génie civil est une problématique majeure pour la sécurité des personnes et la pérennité des ouvrages. L'étude expérimentale permet de comprendre le comportement réel de la structure mais occasionne des problèmes de coût important et d'effet d'échelle souvent inévitable dû aux dimensions des structures. D'un autre côté, l'étude numérique propose une bonne approximation du comportement global mais la représentation précise des phénomènes locaux (fissuration, perte de matière, flambement, grands déplacements) dans les zones fortement endommagées est délicate et souvent insuffisante. Ce travail de thèse propose l'élaboration d'une technique de sous-structuration hybride pour coupler un modèle numérique à une plateforme expérimentale. Ainsi, la partie faiblement endommagée de la structure est modélisée numériquement tandis que la partie fortement endommagée est testée expérimentalement. Cette méthode permet de coupler le réalisme de l'expérimental avec le faible coût numérique sans toutefois perdre en précision. Après avoir élaboré une méthode de couplage hybride peu intrusive pour le code de calcul (Cast3m), un modèle d'endommagement anisotrope adapté aux chargement sismique (effet unilatéral, déformations permanentes) est développé dans le cadre de la thermodynamique des milieux continus. Afin de valider la méthode hybride, une étude expérimentale est menée sur une structure type en béton armé. La fissuration de la partie expérimentale est étudiée grâce à la corrélation d'images. Ce travail expose donc une alternative intéressante aux analyses classiques des structures importantes soumises à des sollicitations complexes. / The seismic analysis of civil engineering structures is a major problem for the safety of the persons and the sustainability of the structures. The experimental study allows to understand the real behavior of the structure but causes problems of important cost and often inevitable scale effect owed in dimension of the structures. On the other hand, the numerical study proposes a good estimate of the global behavior but the accurate modelling of the local phenomena (cracking, losses of material, buckling, large displacements) in the strongly damaged zones is delicate and often insufficient. This work of this thesis proposes the elaboration of a hybrid technique of sub-structuring to couple a numerical model with an experimental platform. So, the weakly damaged part of the structure is numerically modelled whereas the strongly damaged part is experimentally tested. This method allows to couple the precision and the realism of the experimental with the numerical moderate cost without losing however in precision. Having elaborated a few intrusive hybrid method of coupling for the code of calculation (Cast3m), a anisotropic damage model adapted for seismic load (unilateral effect, permanent strains) is developed within the framework of the thermodynamics of the continuous media. To validate the hybrid method, an experimental study is led on a typical reinforced concrete structure. The cracking of the experimental part is studied thanks to images correlation. This work thus exposes an interesting alternative to the classic analyses of the important structures subjected to complex loading.

La presente tesis trata de demostrar que la norma peruana de diseño sismoresitente debe evolucionar y tener mayores exigencias en instituciones de uso esencial, por lo que se evaluará los daños obtenidos mediante un diseño con la Norma E-030 y el ACT-40 ante diferentes niveles sísmicos a los bloques A, B y C de la facultad de Ingeniería Agrícola de la UNALM, para ello en el primer capítulo se explicará la evolución de la norma de diseño sismoresistente E-030 y de algunas normas internacionales como el ATC. En el capítulo 2, se dará a conocer la clasificación de los parámetros de desempeño que tienen las estructuras según el código ATC-40 para el diseño por desempeño. En el siguiente capítulo, se presentarán los bloques diseñados. Mientras que en el capítulo 4 y 5 se realizará un análisis y diseño estructural con la Norma E030 y el ATC-40, respectivamente. Finalmente, en el capítulo 6 Y 7 se presentará una comparación entre los niveles de daños producidos en los elementos mediante el monitoreo de las deformaciones (giros y desplazamientos) comprándolas con los límites de aceptación de las normas mencionadas anteriormente. / This thesis tries to demonstrate that the Peruvian standard of earthquake-resistant design must evolve and have greater demands in institutions of essential use, so that the damages obtained through a design with Standard E-030 and ACT-40 will be evaluated at different levels Seismic blocks A, B and C of the Faculty of Agricultural Engineering of the UNALM, for this in the first chapter the evolution of the E-030 earthquake resistant design standard and some international standards such as the ATC will be explained. In chapter 2, the classification of performance parameters that structures have according to the ATC-40 code for performance design will be announced. In the next chapter, the designed blocks will be presented. While in Chapter 4 and 5 an analysis and structural design will be carried out with Standard E030 and ATC-40, respectively. Finally, in chapter 6 and 7 a comparison will be presented between the levels of damage caused to the elements by monitoring the deformations (turns and displacements) by buying them with the limits of acceptance of the aforementioned standards. / Tesis

Earthquakes are one of the biggest problems in civil engineering all over the world. Due to earthquakes, great disasters in cities with collapsed structures and human losses have been caused. More specific, old buildings that have been built based on old regulations and design building codes do not fulfil anymore the new criteria of seismic designing.In this study, an old building has been evaluated for the seismic load in order to decide if there is a need for strengthening it using retrofitting methods. The seismic evaluation is based on Eurocode 8 and after the application of retrofitting techniques the building fulfilled its seismic design criteria. The existing building is a four-storey, concrete structure that has been built in 1970 and is located in Athens (the capital city of Greece). The seismic evaluation is conducted by using the software Seismostruct.Two analyses are performed in order to evaluate the seismic behavior of the building. First, an eigenvalue analysis is conducted before and after retrofitting. By using this analysis the torsional sensitivity of the building has been checked. Then, using pushover analysis, the comparison of the target displacement (expected displacement of the building for the design seismic action) for each limit state and the displacement of the building when the first member of the building reached the corresponding limit state, is presented. Target displacement must not be greater than this displacement in order to ensure the safety of the building. If the comparison shows that target displacement is greater, the weak links in the facility should be identified and the proper retrofitting method should be applied for the improvement of the seismic behavior of the building. Pushover analysis is conducted before and after the application of retrofitting methods.After performing the eigenvalue and pushover analysis of the existing building it was found that the building was torsional sensitive and shear failures occurred in many beams of the structure. Regarding the bending failures, the target displacement was not greater than the displacement of the building when the first member of the building reached any of the corresponding limit states. Therefore the building was safe against bending failures. With the application of X-shaped steel braces in selected frames, the building had higher stiffness and it was not torsional sensitive but shear failures occurred again in many beams. Furthermore, compressive failures occurred in columns that were connected with the steel braces. Finally, with the application of fibre reinforced plastic jacketing in the members that failed in the previous pushover analysis there were no shear or compressive failures. Finally the structure was safe against seismic actions.The application of retrofitting methods improved the seismic behavior of the building and the structure fulfilled the updated regulations of Eurocode 8 regarding seismic design. This project thesis may give rise to further studies and researches concerning seismic retrofitting and seismic damage prevention.

[pt] Esta dissertação apresenta uma comparação dos métodos utilizados para análise da estabilidade dinâmica de taludes de solo através de métodos pseudoestáticos (equilíbrio limite) e dinâmicos (método dos elementos finitos). Com ambos os métodos foram estudadas as características de estabilidade de 47 perfis de taludes da Costa Verde, faixa litorânea na cidade de Lima, Peru, abrigando importante rodovia ladeada por 8,25 km de taludes íngremes e de grande altura. Nesta região a ocorrência de sismos é freqüente, devido ao fenômeno da subducção da placa de Nazca sob a placa Continental Sul-Americana. O sismo de projeto foi estabelecido em relação a estudos regionais de risco sísmico e o acelerograma utilizado corresponde ao registrado no terremoto de Lima de 03 de outubro de 1974, normalizado para uma aceleração máxima de projeto de 0,33g. Os resultado obtidos pelos métodos pseudo-estáticos e pelo método dos elementos finitos apresentam diferenças em alguns dos perfis analisados, provavelmente porque os métodos pseudo-estáticos geralmente consideram as forças de inércia constantes na fatia e sem mudança de sentido durante o período da excitação sísmica. / [en] This thesis presents a comparison between the methods generally used for dynamic stability analysis of earth slopes, based either on a pseudo-static approach (limit equilibrium method) or on a dynamic approach (finite element method). Forty-seven profiles from the Costa Verde slopes located in Lima, Peru, were analyzed with both classes of methods. In this region seismic activity is quite common, caused by subduction of the Nazca plate into the South American Plate. The design seism was established from regional studies of seismic risks and the accelerogram used in this research corresponds to the seismic records from a major earthquake that hit Lima on October 3rd, 1974, herein normalized with respect to the maximum design acceleration of 0,33g. The results obtained with pseudo-static and the finite element methods presented differences in some specific soil profiles, probably because the pseudostatic methods admit that the inertial forces are constants through a soil slice and there are no changes in direction of the dynamic forces during the period of seismic excitation.

No description available.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: South Africa has some regions which are susceptible to moderate seismic activity. A peak ground acceleration of between 0.1g and 0.15g can be expected in the southern parts of the Western Cape. Unreinforced Masonry (URM) is commonly used as a construction material for 2 to 4 storey buildings in underprivileged areas in and around Cape Town. URM is typically regarded as the material most vulnerable to damage when subjected to earthquake excitation. In this study, a three-storey URM building was analysed by applying seven earthquake time-histories, that can be expected to occur in South Africa, to a finite element model. Experimental data was used to calibrate the in- and out-of-plane stiffness of the URM. A linear modal dynamic analysis and non-linear implicit dynamic analysis were performed. The results indicated that tensile cracking of the in-plane piers was the dominant failure mode. The building relied on the postcracking capacity to resist the 0.15g magnitude earthquake. It is concluded that URM buildings of this type are at risk of failure especially if sufficient ductility is not provided. The results also showed that connection failure must be investigated further. Construction and material quality will have a large effect on the ability of typical URM buildings to withstand moderate magnitude earthquakes in South Africa. / AFRIKAANSE OPSOMMING: Sekere gebiede in Suid-Afrika het ’n risiko van matige seismiese aktiwiteit. Aardbewings met maksimum grondversnellings van tussen 0.1g en 0.15g kan in die suidelike gedeeltes van die Wes- Kaap voorkom. Twee- tot vier-verdieping onbewapende messelwerkgeboue kom algemeen voor in die lae sosio-ekonomiese gebiede van Kaapstad. Oor die algemeen word onbewapende messelwerkgeboue as die gebou-tipe beskou wat die maklikste skade opdoen tydens aardbewings. In hierdie studie is sewe aardbewings, wat tipies in Kaapstad verwag kan word, identifiseer en gebruik om ’n tipiese drie-verdieping onbewapende messelwerkgebou te analiseer. Eksperimentele data is gebruik om die materiaaleienskappe in die in-vlak asook uit-vlak rigtings te kalibreer. Beide ’n liniêre modale en nie-liniˆere implisiete dinamiese analises is uitgevoer. Die resultate dui daarop dat die dominante falingsmode die kraak van in-vlak messelwerk-tussenkolomme is. Die gebou moes sy plastiese kapasiteit benut om die 0.15g aardbewing te kan weerstaan. Die gevolgtrekking is dat dié tipe onbewapende messelwerkgeboue ’n risiko inhou om mee te gee, veral as genoegsame vervormbaarheid nie verskaf word nie. Die resultate toon ook dat konneksie-faling verder ondersoek moet word. Kwaliteit van vakmanskap en van materiaal het ’n groot invoed op die vermoë van onbewapende messelwerkgeboue om aardbewings van matige intensiteit in Suid-Afrika te weerstaan.

[pt] Construção de barragens de terra é uma atividade milenar, empregada com o objetivo de atender às mais diversas necessidades humanas como o armazenamento de água, irrigação, regularização de cursos d água, geração de enregia elétrica, etc. Ao longo da história, o projeto destas obras de terra passou de conceito simples, baseados em técnicas empíricas e regras intuitivas, para as análises modernas que consideram o comportamento da barragem em suas diversas fases de vidas (construção, enchimento do reservatório, regime de plena operação), sob carregados estáticos e sísmicos, condições de contorno complexas e sofisticadas relações constitutivas dos materiais da estrutura e do maciço de fundação. Nesta trabalho a construção, primeiro enchimento do reservatório e a resposta sísmica da barragem de terra de Pomacocha, Peru, são analisados pelo método dos elementos finitos, utilizando o software ABAQUS (versus 6.3). Os campos de tensão e de deslocamentos para diversos estágios de aplicação dos carregamentos estático e sísmico são apresentados, incluindo-se histórias de deformação e de tensão para determinados pontos do corpo da barragem e do solo de fundação. / [en] Dam construction is a millenary activity, carried out with the objective of fulfilling human necessities as water supply, land irrigation, water flow regularization, electric power generation, etc. Along the history, the design of these earthworks evolved from simple concepts, based on empirical techniques and rules of thumb, to modern analyses that consider all phases of a dam s life (construction, first reservoir filling, full operation) understatic and seismic loads, as well as complex boundary conditions and sophisticated constitutive relationships for the structure itself and the foundation mass. In this work, the construction, first reservoir filling and the seismic response of the Pomacocha Dam, located in Peru, are analyzed by the finite element method using the software ABAQUS (version 6.2). At several loading stages the corresponding stress and displacement are presented as well as, for some specific points in the dam body and in the foundation soil, the characteristic stress and strain histories during the static and seismic loads.