An Alternative Scheme to Estimate Displacement from Earthquake-Induced Acceleration for Building Structures

Story drift plays an important role in the safety assessment of building structures as well as the rapid assessment after a seismic event once structural displacement can be properly measured or estimated. For structural health monitoring (SHM), considering their cost, accelerometers are generally used to measure the responses instead of using displacement meters. During the past decade, different techniques have been developed to provide displacement estimation using integration but the conventional integration scheme relies on baseline correction methods to have a reasonable result and none of these techniques can properly estimate the residual displacement. Nevertheless, few of them can have great performance on the structural responses. This study proposes a combination of singular spectrum analysis (SSA) and an integration scheme to estimate the structural displacement directly from the recorded acceleration. Moreover, the proposed method is verified by using the roof responses of the RC specimen recorded during the shaking table test. SSA decomposes the acceleration measurement into approximation and detail parts; the first part are used as weighting factors, and the detail part are integrated twice to have the temporary displacement. Finally, the structural displacement is correctly estimated as well as the induced residual displacement during earthquake excitation.