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Seismic Vulnerability Assessment Of Existing Concrete Highway Iranian Bridges Araliya Mosleh PHD thesis University of Aveiro This report is submitted to the rectory, University of Aveiro, as a PhD project research report, under the scientific supervision of Humberto Varum, Full Professor at the Civil Engineering Department of the University of Porto, cosupervision of José Jara, Full Professor at the Structural Engineering Department of the Universidad Michoacana San Nicolas de Hidalgo, Morelia, Mexico and Mehran Razzaghi, Assistant Professor at the Faculty of Civil Engineering, Islamic Azad University, Qazvin, Iran. منبع دانلود از پیوست Araliya-Mosleh.pdf

Seismic vulnerability of existing buildings Kerstin Lang Institute of Structural Engineering Swiss Federal Institute of Technology Zurich February 2002 Abstract In order to assess the seismic risk for Switzerland, and particularly for the city of Basel, a joint project on the subject of “Earthquake Scenarios for Switzerland” was launched by the Swiss Seismological Service (SED) and the Institute of Structural Engineering (IBK) at the ETH Zurich. The goals of the study are to improve the assessment of seismic hazard, to investigate the vulnerability of the built environment and finally, to combine the results to elaborate risk scenarios as the first fundamental step in the mitigation process. The objective of this work is the evaluation of the seismic vulnerability of existing buildings with a focus on the residential building stock in the city of Basel. Since no major damaging earthquake has occurred in Switzerland in recent times, vulnerability functions from observed damage patterns are not available. A simple evaluation method based on engineering models of the building structures suitable for the evaluation of a larger number of buildings is therefore proposed. First, the general idea of the evaluation method based on nonlinear static procedures is introduced in Chapter 3 which briefly discusses the two key elements of a vulnerability analysis, the capacity (strength and deformation capacity) of a building and the seismic demand. The results are vulnerability functions expressing the expected damage of a building as a function of the seismic input. The application of the evaluation method to unreinforced masonry buildings and to reinforced concrete buildings is discussed in more detail in Chapters 4 and 5 respectively. Special attention is paid to the frame action due to the coupling of the walls by floors and spandrels. Comparisons with test results from model buildings in the case of masonry buildings and with a recently proposed and thoroughly checked deformation orientated method in the case of reinforced concrete buildings show that the proposed method suitably forecasts the capacity of a building. Finally, a comprehensive inventory of the buildings in a small target area in Basel was established based on plans and a street survey. The inventory comprised a total number of 87 buildings which were then assessed using the evaluation method. Based on the results of the assessment, building classes were defined depending on the type of structure and the number of storeys. Corresponding fragility curves were determined, expressing the probability of a building belonging to a certain building class of reaching or exceeding a particular damage grade given a deterministic estimate of the spectral displacement. The classification of the buildings allows an extrapolation of the results to a larger area or to the whole city. A statement on the actual seismic risk, however, is not possible without the knowledge of the local seismic hazard which is not yet available. دانلود منبع Untitled.pdf

A methodology for Determining the Seismic Vulnerability of Old Concrete Highway Bridges by Using Fragility Curves Araliya Mosleh; jose jara; Humberto Varum Past earthquakes have demonstrated that old RC bridges may be seismically vulnerable. Bridge responses during the last decades illustrated the necessity of the seismic assessment of bridges especially those which were designed with old codes. In this research an existing concrete bridge representative of the most common bridges in the highway system in Iran are studied. Push over and nonlinear time history analyses using refined 3-D structural models are performed for each sample. Bridge structural systems are identified and quantified to establish a set of earthquake-site-bridge samples. The superstructure was assumed to remain elastic and the nonlinear behavior in piers was modeled by assigning plastic hinges in columns. The soil flexibility was considered by using elastic spring elements. Displacement ductility and peak ground acceleration (PGA) were selected as seismic performance indicator and intensity measure, respectively. Ten time history records from the past earthquakes were selected. They were scaled and applied incrementally to the 3-D model to evaluate seismic performance of the bridge. Furthermore, bridge damage states were defined and the probabilistic characteristics of structural capacity corresponding to each damage state were established. Then, the conditional probabilities of specific structural demand to exceed the structural capacity were computed and the results were displayed as fragility curves. منبع دانلود JSEG331427657400.pdf

Analytical Evaluation of Uncertainty Propagation in Seismic Vulnerability Assessment of Tehran Using GIS Original Article, A2 Jahanpeyma MH, Delavar M.R. Journal. Civil Eng. Urban. 1(1): 05-09. 2011. ABSTRACT: One of the properties of geospatial information systems is their use in supporting spatial decision making under uncertainty. It is a complex process which is considered in different situations. The existence of uncertainty in geospatial data and various analyses has the potential to expose users to undesirable consequences in their decision making. Nowadays, natural disasters, particularly earthquake, are among the most important disturbances to sustainable development of countries and governments try to manage them in an optimum manner. They would typically try to decrease the amount of financial damages and loss of lives that would occur because of the events. In this research, geospatial information science/system has been implemented to estimate the seismic vulnerability and its probable damages for a particular scenario in Tehran. We applied fuzzy logic concepts to well-known analytical hierarchical process for the damage assessment. Based on this modified approach we developed a hierarchy of effective factors in earthquake vulnerability due to definition of their priorities against a given earthquake scenario.The effect of uncertainty in geospatial data and analysis functions which are applied in estimating Tehran seismic vulnerability would affect the quality of decision making for estimating the damages. In this paper, we analyzed the implemented geospatial data of population statistics, building information, maps, digital terrain models, and satellite images in the process of studying Tehran’s seismic vulnerability. In this research, we used Monte Carlo simulation approach for uncertainty modeling. We compute the statistical parameters for seismic vulnerability in various iterations of Monte Carlo process. After that we extract the relationship between the number of Monte Carlo process and relative variation of seismic vulnerability’s layer variance. For instance, in order to achieve double precision, the number of iterations must increase four times. Keywords: Uncertainty, GIS, Seismic Vulnerability, Analytic Hierarchy Process, Monte Carlo Simulation منبع: [Hidden Content] دانلود: [Hidden Content],%20A2,final.pdf JCEU, A2,final.pdf

NONLINEAR DYNAMIC ANALYSIS OF CHIMNEY-LIKE TOWERS M.R. Tabeshpour* Faculty of Engineering, Sabzevar Tarbiat Moallem University, Sabzevar, Iran Received: 5 September 2010, Accepted: 5 July 2011 ABSTRACT Evaluation of seismic vulnerability of very flexible structures such as high-rise petrochemical and refinery stacks (chimney) and power plant chimneys is a challenging problem in earthquake engineering. Their equipments and structures are often considered as vital facilities and thus they must be fully functional after even very strong ground motions. From other point of view, numerical modeling of such mega-structures with numerous elements may not allow to consider all details of mechanical characteristics of consisting materials, particularly nonlinear performance of elements during large deformations. Therefore, a simplified model corresponding to dynamic characteristics of whole structure is substantially needed to investigate seismic performance and failure modes of these essential structures subjected to strong ground motions. The procedure for developing a 2-D simplified nonlinear model based on moment-curvature in some plane-sections of a 3-D sophisticated model but linear system having almost identical dynamic properties is discussed. If micro elements be used for structural modeling of the chimney like structures, static nonlinear analysis or dynamic linear analysis will be economically suitable for assessment investigation. But of the most important problems in earthquake behavior of the structures is hysteretic behavior of material and section properties. The significance of this study, if any, is mainly concentrated on model simplification that provides sufficient accuracy based on a nonlinear discrete model. Tous power-plant chimney is investigated numerically as an example. Keywords: High-rise structures; seismic vulnerability; damage index; nonlinear model Nonlinear dynamic analysis of chimney-like towers Tabeshpour_NONLINEAR-DYNAMIC_2010-2012.pdf