torsion of many symmetric structures, which were designed based on the seismic codes, is due to their asymmetricity induced during inelastic behavior. although the structure was designed symmetrically assuming elastic based criteria, different factors such as material inconsistency in structure, construction details discrepancy and construction errors may result in asymmetric behavior in inelas...

bridges, as an essential part of transportation system, play a special role in economy, politic and military all around the world. serviceability of bridges is of high importance especially in emergencies, helping injured people and proportioning transportation after earthquakes. earthquake regulation codes, normally suggest linear methods to conduct the analysis, and nonlinear analysis is bare...

accurate identification of seismic hazard and the estimation of associated seismic demands are the key components in the performance-based seismic design (pbsd). although nonlinear time history (nth) analysis is the most precise procedure to evaluate the seismic demands of buildings structures, it is relatively complex and time-consuming for routine applications. nonlinear static procedures (ns...

the proposal lateral load pattern for pushover analysis is given in two forms for symmetric concrete buildings: 1-(x/h)0.5 for low-rise and mid-rise buildings, 2- sin(πx/h) for high-rise buildings. these two forms give more realistic results as compared to conventional load patterns such as triangular and uniform load patterns. the assumed buildings of 4, 8, 12, 16, 20 and 30 story concrete bui...

This paper proposes a simplified analytical model for seismic response prediction of concentrically braced frames. In the proposed approach, a multistory frame model is reduced to an equivalent shear-building one by performing a static pushover analysis. The conventional shear-building model has been improved by introducing supplementary springs to account for flexural displacements in addition...

In the present paper, the focus is on the evaluation of steel dual-system frame buildings using four main types of structural analysis (Linear Static, Linear Dynamic, Nonlinear Static and Nonlinear Dynamic Analyses) with regard to "Seismic Rehabilitation Code for Existing Buildings in Iran" (based on FEMA 273 and 356) where the first two authors of the article tend to follow the previous work (...

The design of earthquake-resistant buildings starts with defining the maximum lateral earthquake forces or their resultant. The amount of these forces depends on various factors, including coefficient of system behavior which depends on overstrength and its ductility. In this study, a method is presented for designing an earthquake-resistant system in which the distribution of lateral forces is...

pushover analysis is a simplified nonlinear analysis technique that can be used to estimate the dynamic demands imposed on a structure under earthquake excitations. one of the first steps taken in this approximate solution is to assess the maximum roof displacement, known as target displacement, using the base shear versus roof displacement diagram. that could be done by the so-called dynamic p...

this paper presents the numerical analysis of seismic soil-pile-superstructure interaction in soft clay using free-field soil analysis and beam on winkler foundation approach. this model is developed to compute the nonlinear response of single piles under seismic loads, based on one-dimensional finite element formulation. the parameters of the proposed model are calibrated by fitting the experi...

Concentrically braced frames and eccentrically braced frames are efficient seismic resistant systems but they are generally prone to develop storey collapse mechanisms. As underlined in some previous papers with regard to eccentrically braced frames, this tendency depends on the overstrength factors and damage distribution capacity factors resulting from the use of common design procedures. In ...