Endurance time (ET) method is a relatively new performance-based earthquake method for structural evaluation and design. In this method, the structure is subjected to a gradually intensifying accelorogram(s) and its performance is assessed based on the maximum time duration that it can meet the specified performance objectives. Using moment-resisting and braced frames which are rehabilitated by...

Most of oil and gas offshore platforms are located in the seismic regains. So, Seismic vulnerability evaluation of the offshore platforms is one of the most important and vital issues in the structural systems. In this study, jacket type offshore platforms are studied by incorporating the pushover analyses and nonlinear time history analyses, in such a way that, first some push over analyses ar...

Numerical simulation of structural response is a challenging issue in earthquake engineering and there has been remarkable progress in this area in the last decade. Endurance Time (ET) method is a new response history based analysis procedure for seismic assessment and structural design in which structures are subjected to a gradually intensifying dynamic excitation and their seismic performanc...

The seismic design of bridge structure is influenced by the bi-directional excitation phenomenon. The bi-directional effects have been ignored in most of the past studies. The calculation of maximum isolator displacements (as per the equation prescribed by AASHTO) also ignores the bi-directional effects of ground motion. In the formulation, the coupled behaviour of the isolation systems has als...

In this paper, the mechanical behaviors of bridges with unseating prevention devices in the superstructure were investigated. These devices can prevent bridge from unseating and divert most of the seismic forces from transferring to the bridge columns. The models of the rubber bearing, restrainer, and shear key were proposed and implemented into the SAP 2000 to obtain the seismic response of th...

in recent years, seismic evaluation and vulnerability of the existing buildings, that have been designed based on an earlier seismic design code or designed without seismic design criteria, has been very important. in this paper, the seismic evaluation and vulnerability of concrete buildings, using an old 5- story building with shear walls as an example has been discussed. for this building, fi...

High tall buildings are more susceptible to dynamic excitations such as wind and seismic excitations. In this paper, design procedure and some current applications of tuned mass damper (TMD) were studied. TMD was proposed to study response of 20 storey height building to seismic excitations using time history analysis with and without the TMD. The study indicates that the response of structur...

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...

In this study, the effect of deep excavation on the seismic response of RC moment resisting building systems has been studied. Deep excavation can cause significant changes in the stress and strain levels of soil environment and also changes in the propagation of seismic waves. This leads to permanent displacements in the foundation system. In this study, three RC building systems, i.e. 5, 10, ...

The significance of the seismic rotational components have been overlooked in the seismic evaluation of structural behavior. As researchers have measured seismic components more accurately using sensitive rotational velocity sensor, it was observed that the magnitude of rotational components is considerable and could not be neglected. Hence, some parts of seismic damage or failure of structures...