عنوان مجله
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STRUCTURAL ENGINEERING AND MECHANICS
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چکیده
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Inelastic static pushover analysis has been used in the academic-research widely for seismic analysis of structures.
Nowadays, the variety pushover analysis methods have been developed, including Modal pushover, Adaptive pushover, and
Cyclic pushover, in which some weaknesses of the conventional pushover method have been rectified. In the conventional
pushover analysis method, the effects of cumulative growth of cracks are not considered on the reduction of strength and
stiffness of RC members that occur during earthquake or cyclic loading. Therefore, the Cyclic Pushover Analysis Method (CPA)
has been proposed. This method is a powerful technique for seismic evaluation of regular reinforced concrete buildings in which
the first mode of them is dominant. Since the bridges have different structures than buildings, their results cannot necessarily be
attributed to bridges, and more research is needed. In this study, a cyclic pushover analysis with four loading protocols
(suggested by valid references) by the Opensees software was conducted for seismic evaluation of two regular reinforce concrete
bridges. The modeling method was validated with the comparison of the analytical and experimental results under both cyclic
and dynamic loading. The failure mode of the piers was considered in two-mode of flexural failure and also a flexural-shear
failure. Along with the cyclic analysis, conventional analysis has been studied. Also, the nonlinear incremental dynamic analysis
(IDA) method has been used to examine and compare the results of pushover analyses. The time history of 20 far-field
earthquake records was used to conduct IDA. After analysis, the base shear vs. displacement in the middle of the deck was
drawn. The obtained results show that the cyclic pushover analysis method is able to evaluate an accurate seismic behavior of
the reinforced concrete piers of the bridges. Based on the results, the cyclic pushover has proper convergence with IDA. Its
accuracy was much high
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