Nuestro país se encuentra ubicado en una zona de alta actividad sísmica, por ello es importante que los ingenieros civiles tengan una adecuada capacidad para realizar análisis de vulnerabilidad sísmica y comprendan la importancia de la prevención. En la presente tesis analizamos los diferentes escenarios de daño sísmico para edificios de concreto armado organizados por tipología de número de pisos. Para el desarrollo de la presente investigación utilizamos dos Software, el primer software de simulación sísmica, en el cual modelamos la muestra de edificaciones de concreto armado que representan el distrito de Santiago de Surco, para luego analizarlo con un sismo de tiempo historia que simula varias magnitudes del mismo sismo amplificado con aceleraciones del suelo que varían de 0.1g a 1.0g, con el objetivo de obtener cada vez mayores desplazamientos, y de esa manera mayores niveles de daño mediante la metodología Hazus M-H. Luego estos valores expresarlos en cuadros de curvas de fragilidad sísmica con cuatro tipos de niveles de daño. El Segundo Software que utilizamos es el Sistema de Información Geográfica (SIG), con este programa sistematizamos los datos obtenido de la curva de fragilidad para mostrar mapas de niveles de daño para distintos escenarios sísmicos que muestren el comportamiento de los edificios al ocurrir un evento sísmico. Our country is located in a zone of high seismic activity, it is important that civil engineers have adequate capacity for analysis of seismic vulnerability and understand the importance of prevention. In this thesis we analyze the different scenarios of seismic damage to reinforced concrete buildings organized by type of number of floors. For the development of this research we use two software, the first seismic simulation software, which model the sample of reinforced concrete buildings representing Santiago de Surco, and then scan it with an earthquake simulating various weather history amplified earthquake magnitudes thereof with ground accelerations ranging from 1.0g 0.1ga, in order to obtain increasing displacement, and thus higher levels of damage by HAZUS MH methodology. Then these values express them in boxes seismic fragility curves with four types of damage levels. The second software we use is the Geographic Information System (GIS), with this program systematize data obtained fragility curve to display maps for different levels of damage scenarios showing the seismic performance of buildings to a seismic event occur.

Time history-analyses of building structures have been used for a quite long time for research at universities. Considering the advantage of time-history analysis relative to the equivalent static force method, the National Building of Canada and other modern building codes around the world require the use of time-history analysis in the design of specified types of buildings located in seismic regions. One of the main issues in the use of time-history analysis is related to the selection and scaling of the seismic excitations (i.e., accelerograms) to be compatible with the design spectrum for the location considered. Currently, both recorded (i.e., “real”) accelerograms and artificial accelerograms are used in the analyses. The objective of this study is to determine the effects of the selection and scaling of seismic excitations on the response of reinforced concrete frame buildings. Three reinforced concrete frame buildings with heights of 4 storey, 10 storey and 16 storey, designed for Vancouver (high seismic zone) were used in this study. Five sets of seismic excitations were used in the analysis – one set of “real” accelerograms, and four sets of artificial accelerograms obtained by different methods. All sets were scaled to be compatible with the design spectrum for Vancouver. Both linear and nonlinear time history analyses were conducted on the buildings considered. Interstorey drifts and storey shear forces were used as response parameters. The results from the linear analysis show that both the interstorey drifts and the shear forces are affected significantly by the type of the excitation set. Similarly, the effects of the type of the seismic excitations on the drifts from nonlinear analysis are substantial. On the other hand, the influence of the excitation sets on the storey shears from nonlinear analysis are quite small. Based on the results from this study, sets of scaled real records are preferred for use in time-history analysis of building structures. If such records are not available, then sets of simulated accelerograms based on the regional seismic characteristics should be used.

Nonlinear time history analysis is increasingly being used in the design of tall steel structures, but member sizes still must be determined by a designer before an analysis can be performed. Often the distribution of story strength is still based on an assumed first mode response as determined from the Equivalent Lateral Force (ELF) procedure. For tall buckling restrained braced frames (BRBFs), two questions remain unanswered: what brace distribution will minimize total brace area, while satisfying story drift and ductility limits, and is the ELF procedure an effective approximation of that distribution? In order to investigate these issues, an optimization algorithm was incorporated into the OpenSees dynamic analysis platform. The resulting program uses a genetic algorithm to determine optimum designs that satisfy prescribed drift/ductility limits during nonlinear time history analyses. The computer program was used to investigate the optimized distribution of brace strength in BRBFs with different heights. The results of the study provide insight into efficient design of tall buildings in high seismic areas and evaluate the effectiveness of the ELF procedure.

The controlled rocking heavy timber wall (CRHTW) is a high-performance structural solution that was first developed in New Zealand, mainly considering Laminated Veneer Lumber (LVL), to resist high seismic loads without sustaining structural damage. The wall responds in bending and shear to small lateral loads, and it rocks on its foundation in response to large seismic loads. In previous studies, rocking has been controlled by both energy dissipation elements and post-tensioning, and the latter returns the wall to its original position after a seismic event. The controlled rocking response avoids the need for structural repair after an earthquake, allowing for more rapid return to occupancy than in conventional structures. Whereas controlled rocking walls with supplemental energy dissipation have been studied before using LVL, this thesis proposes an adapted CRHTW in which the design and construction cost and complexity are reduced for low-to-moderate seismic hazard regions by removing supplemental energy dissipation and using cross-laminated timber (CLT) because of its positive economic and environmental potential in the North American market. Moreover, whereas previous research has focussed on direct displacement-based design procedures for CRHTWs, with limited consideration of force-based design parameters, this thesis focusses on force-based design procedures that are more common in practice. A design and analysis process is outlined for the adapted CRHTW, based on a similar methodology for controlled rocking steel braced frames. The design process includes a new proposal to minimize the design forces while still controlling peak drifts, and it also includes a new proposal for predicting the influence of the higher modes by referring to previous research on the capacity design of controlled rocking steel braced frames. Also, a numerical model is outlined, including both a baseline version and a lower-bound model based on comparison to experimental data. The numerical model is used for non-linear time-history analysis of a prototype design, confirming the expected performance of the adapted CRHTW, and the model is also used for incremental dynamic analyses of three-, six-, and nine-storey prototypes, which show a low probability of collapse. / Thesis / Master of Applied Science (MASc) / The controlled rocking heavy timber wall (CRHTW) is a high-performance structural solution that was developed to resist high seismic loads without sustaining structural damage. The wall responds in bending and shear to small lateral loads, and it rocks on its foundation in response to large seismic loads. In previous studies, rocking has been controlled by both energy dissipation elements and post-tensioning; the latter returns the wall to its original position after a seismic event. This controlled rocking behaviour mitigates structural damage and costly repairs. This thesis explores the value of an adapted CRHTW in which the design and construction costs and complexity are reduced for low-to-moderate seismic hazard regions by using post-tensioning but no supplemental energy dissipation. A design and analysis process is outlined; numerical analysis confirms the expected performance of the adapted CRHTW; and the system is shown to have a low probability of collapse.

No description available.

A major concern for geotechnical engineers is the ability to predict how a soil will react to large ground motions produced by earthquakes. Of all the different types of soil, liquefiable soils present some of the greatest challenges. The ability to quantify the degradation of a soil's shear modulus as it undergoes liquefaction would help engineers design more reliably and economically. This thesis uses ground motions recorded by an array of downhole accelerometers on Port Island, Japan, during the 1995 Kobe Earthquake, to quantify the shear modulus of sand as it liquefies. It has been shown that the shear modulus of sand decreases significantly as it liquefies, apparently decreasing in proportion to the increasing excess pore water pressure ratio (Ru). When completely liquefied, the shear modulus of sand (Ru = 1.0) for a relative density of 40 to 50% is approximately 15% of the high-strain modulus of the sand in its non-liquefied state, or 1% of its initial low-strain value. Presented in this thesis is an approach to modeling the shear modulus degradation of sand as it liquefies. This approach, called the "degrading shear modulus backbone curve method" reasonably predicts the hysteretic shear stress behavior of the liquefied sand. The shear stresses and ground accelerations computed using this method reasonably matches those recorded at the Port Island Downhole Array (PIDA) site. The degrading shear modulus backbone method is recommended as a possible method for conducting ground response analyses at sites with potentially liquefiable soils.

Quantitative and qualitative assessment of the seismic risk to highway bridges is crucial in pre-earthquake planning, and post-earthquake response of transportation systems. Such assessments provide valuable knowledge about a number of principal effects of earthquakes such as traffic disruption of the overall highway system, impact on the regions' economy and post-earthquake response and recovery, and more recently serve as measures to quantify resilience. Unlike previous work, this study captures unique bridge design attributes specific to California bridge classes along with their evolution over three significant design eras, separated by the historic 1971 San Fernando and 1989 Loma Prieta earthquakes (these events affected changes in bridge seismic design philosophy). This research developed next-generation fragility curves for four multispan concrete bridge classes by synthesizing new knowledge and emerging modeling capabilities, and by closely coordinating new and ongoing national research initiatives with expertise from bridge designers. A multi-phase framework was developed for generating fragility curves, which provides decision makers with essential tools for emergency response, design, planning, policy support, and maximizing investments in bridge retrofit. This framework encompasses generational changes in bridge design and construction details. Parameterized high-fidelity three-dimensional nonlinear analytical models are developed for the portfolios of bridge classes within different design eras. These models incorporate a wide range of geometric and material uncertainties, and their responses are characterized under seismic loadings. Fragility curves were then developed considering the vulnerability of multiple components and thereby help to quantify the performance of highway bridge networks and to study the impact of seismic design principles on the performance within a bridge class. This not only leads to the development of fragility relations that are unique and better suited for bridges in California, but also leads to the creation of better bridge classes and sub-bins that have more consistent performance characteristics than those currently provided by the National Bridge Inventory. Another important feature of this research is associated with the development of damage state definitions and grouping of bridge components in a way that they have similar consequences in terms of repair and traffic implications following a seismic event. These definitions are in alignment with the California Department of Transportation's design and operational experience, thereby enabling better performance assessment, emergency response, and management in the aftermath of a seismic event. The fragility curves developed as a part of this research will be employed in ShakeCast, a web-based post-earthquake situational awareness application that automatically retrieves earthquake shaking data and generates potential damage assessment notifications for emergency managers and responders. / Errata added at request of advisor and approved by Graduate Office, March 15 2016.

O presente trabalho faz uma análise do movimento do software livre, um importante movimento de conotação mundial criado para superar as barreiras impostas ao fluxo do conhecimento pela propriedade privada das idéias. O nosso foco não é a luta entre as duas formas de tecnologia de software, livre e proprietária, mas compreender melhor a dinâmica do movimento que foi criado por Richard Stallman. Assim, o objetivo é mostrar que apesar de sua globalidade, o software livre não é recebido e desenvolvido da mesma forma, ao contrário, em cada país ele é recriado a partir das práticas e concepções políticas acerca do papel da tecnologia para o desenvolvimento social e econômico. Para justificar nossa hipótese, escolhemos analisar a América Latina, um continente que enxergou no software quando livre, através de seus governantes, a ferramenta capaz de proporcionar o desenvolvimento e até a independência nacional frente aos países desenvolvidos. Como contraponto de análise, discorremos também sobre o impacto da tecnologia livre, ou melhor, de código aberto, no país ícone da sociedade informacional, os Estados Unidos, onde as empresas privadas (em especial Apple e Google) e as universidades impulsionam a criação e a inovação tecnológica. No confronto analítico entre o poder de criação estatal x privado ou livre x aberto, a junção privado/aberto foi mais incisiva na criação de um terceiro modo de produção de software, que chamamos de híbrido - meio fechado, meio aberto. Esse software híbrido parece ser o modelo que manterá os países hegemônicos na liderança da corrida tecnológica. / The present work performs an analysis of the free software movement, an important movement worldwide developed to overcome the barriers imposed to the knowledge flow by the idea private property. Our focus is not the fight between the two software technology forms, free and proprietary, but to understand in a better way the dynamic of the movement created by Richard Stallman. Thus, the purpose is to show that, despite its globality, the free software is not received and developed the same way, on the contrary, in every country it is recreated from the practices and political conceptions about the technology role for the social and economical development. In order to justify our hypothesis, we chose to analyze Latin America, a continent which saw in the free software, by means of its governors, a tool capable of providing the development and even the national independence before the developed countries. As an analysis counterpoint, we also approached the free technology impact, that is, the open source, in the informational society icon country, the United States, where the private companies (especially Apple and Google) and the universities trigger the technological development and innovation. In the analytical confrontation between the state vs. private or free x open development power, the private/open junction has been more assertive at a third software production means, which we call \"hybrid\" - half closed, half open. Such hybrid software seems to be the model which will keep the hegemonic countries in the technological race leadership.

In reality, dynamic response of a structure supported on a compliant soil may vary significantly from the response of same structure when supported on a rigid base. A parametric study is conducted for the analysis of the variation in the global and the local deformation demands caused by the inertial soil-structure interaction effects. For the purposes of the study, nonlinear dynamic analyses are performed on 7 steel moment-resisting frame models, which are prepared by the virtue of fixed-base and flexible-base (interacting) conditions. Foundation is modeled with the Truncated Cone Model (Wolf, 1994) with the frequency independent coefficients. Free-field earthquake acceleration records are selected to conform to NEHRP equivalent Site Classes C and D. The study is limited to the structures founded on surface rigid mat foundations subjected to vertically propagating horizontally polarized coherent shear waves. Statistical analysis based on multiple linear regression procedure is performed to represent the variation in the response. Within the scope of the study, the wave parameter and the aspect ratio are observed to be directly proportional to the variation in the response, as a general trend. Maximum beneficial contribution of the SSI is found to be 6% in both global and local deformation demands. In addition, the contribution of inertial interaction effects is found to be in a decreasing trend for the increasing levels of ductility demands. Finally, upper limits of wave parameter for H/R=0.5, 1, 2 and 3 are calculated where the variation in the demands are capped at 1.0.

Prior to this study, to our best knowledge, no cast-in-place, older-type RC building has ever been subjected to near-field strong ground motions from three major earthquakes. This happened in an indirect way in Turkey over a time span of eleven years. Three identical buildings belonging to Ministry of Public Works and Resettlement (MPWR) that had been built to the same design templates, experienced March 13th 1992 Erzincan earthquake in Erzincan, November 12th 1999 D&uuml / zce earthquake in Bolu and May 1st 2003 Bing&ouml / l earthquake in Bing&ouml / l, respectively. The ground motion sensor stations were fortuitously nearby in an adjacent single-story building in Bolu and Bing&ouml / l. The station in Erzincan was in a single-story building about 2 km away from the case study building but we assume that the record applies to the building there. These three data represent characteristics of near-field ground motions and the distance of the sensor stations to the nearest fault trace was less than 10 km. The buildings sustained varying degrees of damage during the earthquakes and their damage survey was employed through site investigations. Given that the damage information, input motions, design drawings and material properties of the buildings are all known, this provided an opportunity to predict the structural damage to these buildings by proper modeling using the tools of current computational performance assessment procedures. In this circumstance, three dimensional (3D) analytical models of the MPWR buildings have been performed. Bi-directional excitations have been applied to the models by nonlinear time history analyses (NTHA). The results illustrate that NTHA are capable of indicating the occurrence of shear failure in captive columns / however, they overestimate the global damage level for all buildings. The overestimation is more significant in Erzincan case where the building sustained a pulse-type motion without significant distress.