Endurance time method for multi-component analysis of steel elastic moment frames

The Endurance Time (ET) method is a time history-based dynamic analysis procedure which uses special intensifying acceleration functions for evaluation of the seismic response of structures. One of the potential applications of the ET method is in the three-dimensional analysis of buildings under multi-directional excitations. In this paper, considering horizontal components of excitation, an algorithm for the multi-component analysis of building structures by the ET method is proposed, and results of the ET method for various steel moment frames with 1 to 7 stories are compared with results from time history analysis with real earthquakes. Results show that based on recommendations of structural codes for bi-directional time history analysis, which requires applying horizontal components of earthquakes simultaneously, the ET method can be used to predict the seismic response of structures with appropriate approximation.