Estimation of relative displacement of two adjacent asymmetric structures

The most straightforward method to mitigate seismic pounding damage to adjacent structures is to provide adequate separation distance between them to completely preclude pounding during strong shaking. Many studies on the necessary separation distance between adjacent structures have been reported recently. Seismic codes around the world also specify the minimum required separation distances. However, all those required separations were derived by considering only the lateral responses of structures. For asymmetric structures with coupled torsional–lateral responses, the required separations are not well investigated. This paper presents some parametric study results on the relative displacement of adjacent asymmetric structures by considering their coupled torsional–lateral responses. Random vibration method is employed in the analysis. Both elastic and inelastic responses are considered. Effects of vibration frequencies, torsional stiffness and eccentricities of adjacent structures on their relative displacements are investigated. Numerical results are presented in dimensionless form and are discussed with respect to the current code specifications.