Physically‐Based Method for Predicting Peak and Residual Interstory Drift Ratios of Buildings From Measured Acceleration Responses

A physically‐based method was developed to predict peak and residual interstory drift of buildings by recovering interstory drift time histories with residual trends from measured absolute acceleration time histories. In this method, the oscillating part of an interstory drift time history without a residual trend is predicted using a conventional baseline correction scheme. The residual trend is then predicted separately by using an accelerometer‐specific empirical equation developed from test data and a structure‐specific transformation matrix derived using a structural finite‐element model and the force analogy method. The developed accelerometer‐specific empirical equation predicts the plastic rotation of joints with installed accelerometers from the acceleration shift value of a low‐pass‐filtered relative acceleration. The residual trend of the interstory drift time history can then be obtained using these predicted time histories of plastic rotations and the structure‐specific transformation matrix. To validate the developed method, shaking table tests were performed for two different three‐story steel frames. The interstory drift time histories of each floor with residual trends could be recovered at various excitation levels, and the peak and residual interstory drift ratios could be predicted with high accuracy for most cases. The estimation errors for each excitation were acceptable for preliminary post‐earthquake rapid structural damage assessments. Compared with conventional signal‐processing‐based methods, the proposed method is easier to implement in rapid structural damage assessment for real buildings. The proposed method is automatic, does not require case‐by‐case parameter adjustment, and ensures that the uncertainties of the predicted peak and residual interstory drifts are well‐constrained. Summary A new method for predicting peak and residual interstory drift ratios of buildings from measured acceleration responses subjected to an earthquake. Estimation of plastic rotation from lowpass filtered acceleration shift. Residual trend recovery of interstory drift time history based on the force analogy method. Advantages of low uncertainty and automation without parameter adjustment.