Effect of Causality Filters of Accelerograms on Low-Rise Structure Responses

Abstract

Because output accelerographs always contain noise, to use data in analysis and design of structures, there is a need for rational correction of raw data. These corrections include baseline correction, instrument correction, and filtration practices. In this paper, a 1-story steel moment frame and 3-story steel moment frame as benchmark have been used to study the effect of causal and acausal filtration. Accelerogram records have been used from five stations in successive earthquakes of Ahar-Varzaghan on August 11, 2012, and six stations that recorded the Sarpole-Zahab earthquake on November 12, 2017, for incremental dynamic analysis (IDA). The results show that the behavior of the representative structures by process of correction with causal and acausal filters in the elastic region, are roughly similar. Also the IDA summary curves show that the structures is subjected to higher intensity in acausal filters than in causal ones, so causal filtration in nonlinear analysis of low-rise structures seems to have more conservative responses in comparison with acausal one, not more than 15%.