Investigation of Irregular Mass in Height for Structures using Incremental Dynamic Analysis (IDA)

Document Type : Research Paper


1 M.Sc. of Structural Engineering, Department of Civil Engineering, Ahar Branch, Islamic Azad University, Ahar, Iran.

2 Assistant Professor, Department of Civil Engineering, Ahar Branch, Islamic Azad University, Ahar, Iran.


In this paper, the effects of irregular mass in height for structures has been investigated. To achieve this goal, two five and ten stories concrete moment resisting frames are modeled using Seismostruct software and subjected to seven different accelerograms. To evaluate the seismic performance of the studied structures, incremental dynamic analysis (IDA) has been used. The results reveals that the seismic capacity of the irregularly structures reduced, and therefore, it is suggested that mass irregularity in height be avoided as much as possible.


Main Subjects

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