Abstract

Torsional irregularity leads to increased unequal displacements at the extremes of the building and may cause distress in the lateral load resisting elements at the edges. Torsional irregularity is caused by plan asymmetry, asymmetrical distribution of mass and stiffness, asymmetrical configuration of the lateral load resisting systems. In the present study, a model G+2 storey was considered to analyze the torsional behavior of the structure subjected to base excitation using shake table test setup. A physical model was constructed and tested to study its torsional behavior under seismic loading. A similar model was developed and analyzed using SAP-2000 software. From the experimental test results, it was observed that, three translational modes and two torsional modes of vibrations were found to exist in the structure.

Key words: Dynamic loading, Torsion, stiffness, symmetrical structures, shake table.