SEISMIC PERFORMANCE ASSESSMENT OF THE TORSIONAL EFFECT IN ASYMMETRIC STRUCTURES USING PUSHOVER AND NON-LINEAR TIME HISTORY METHOD

Nischith S, Avinash Gornale, Sowjanya G V, B G Naresh Kumar

Abstract: In the recent time we come across many structures which are irregular in shape, this type of cannot be avoided due to the functional and architectural requirements. These type of structures have irregular distribution of centre of mass and centre of rigidity which causes the torsional effect on the structures which is one of the most important factor influencing the seismic damage of the structure. Structures with asymmetric distribution of mass and rigidity undergoes torsional motions during earthquake. To assess the torsional effect on the structures in the present study four types of structures are considered with varying eccentricity subjected to Pushover Analysis and Non-Linear Time History Analysis. The performance of the structures are assessed as per the procedure prescribe in ATC-40 and FEMA-356. The analysis of the structural models is done in ETABS. The results have shown that the structures with less eccentricity and in the direction of the columns orientation are performing well, also ductility, drift, and lateral displacement depends on the eccentricity of the structures.

Keywords: Symmetric Structure, Asymmetric Structure, Pushover Analysis, Non-Linear Time History Analysis

DOI: https://doi.org/10.15623/ijret.2015.0407055