Uncertainties in seismic response of a torsional irregular structure

Torsional effects may significantly modify the seismic response of asymmetric buildings. This is due to the influence of several complex and difficult parameters to apprehend. The present paper deals with the influence of the input parameters on the seismic response of an asymmetric structure. Thus, several nonlinear dynamic analyses are performed in order to evaluate the effects of torsion on the seismic response of an asymmetric structure and shown their preponderances. The importance of the uncertain characteristics of the input seismic motion on the structural damage and the sensitivity of the response to the input parameters are assessed by a probabilistic analysis. The influence of these parameters is quantified through the use of partial correlation coefficient (PCC). The response in terms of roof displacement is calculated and used to construct fragility curves in order to quantify the probability of different damage levels according to the input motion.