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At the present study, application of endurance time analysis (ETA) method in seismic evaluation of arch dams is investigated. ETA is a time-history based dynamic pushover procedure, which utilizes a set of predesigned intensifying acceleration functions to estimate the responses of the structural systems in various seismic excitation levels. Dez dam was chosen as the case study and all contraction and peripheral joints were modeled based on as-built drawings. The reservoir was modeled as a compressible medium and the foundation was assumed to be massless. Results show that ETA method is able to estimate dynamic responses of the dam with acceptable accuracy in comparison with time history... 

One of the methods in limiting tensile stresses in arch dams and removing stress concentrations at the dam-foundation interface is setting the dam body on a concrete saddle called a Pulvino. In the present study, the effects of Pulvino and peripheral joints on the static behavior and seismic performance of arch dams are investigated. Dez Dam with a height of 203 m was selected as a case study and all contraction joints of the dam body were modeled using the discrete crack approach based on as-built drawings. Also, the surrounding rock was modeled as a mass-less medium tied to Pulvino. The dam-reservoirfoundation system was analyzed under static loads accounting for stage construction... 

At present study, Endurance Time (ET) method that is a new dynamic pushover procedure is introduced and its application in predicting concrete arch dam behavior in linear domain is investigated. In this method structure is subjected to gradually intensifying acceleration functions. DEZ arch dam was selected as case study. FE model of dam-reservoir-foundation was excited in three levels of MCL, MDL, DBL using six records scaled based on design spectrum of the site and results were compared with those obtained from ET analyses. It was found that results obtained from ET method at equivalent target time are in good agreement with extreme results obtained from exciting the system using natural... 

In the present paper, the nonlinear seismic behavior of a concrete gravity damreservoir- massed foundation system is studied focusing on the foundation material nonlinearity. For this purpose, a finite element program utilizing the elasto-plastic formulation for the foundation medium is provided considering the tensile and shear failure modes. Hoek-Brown and Mohr Coulomb criteria are used as the yield and plastic potential function of the shear failure mode, respectively; and in the tensile failure mode, various levels of the tensile strength are applied to the foundation. Bearing capacity is studied considering the localized plastic elements and forming the sliding path by plastic elements... 

A new method for seismic analysis of containers in three-dimensional space is introduced in which the effects of both impulsive and convective components and their corresponding damping are accounted for in time domain. A case study is performed to investigate the behaviour of a concrete rectangular container under the effects of horizontal and vertical ground motions using the scaled earthquake components of the 1940 El-Centro earthquake record. Two-dimensional behaviour of the tank is assumed. The results of the study are compared with those obtained using the current practice and those determined from finite element (FE) analysis based on a lumped mass model. The results of the FE...