STUDY ON THE INFLUENCE OF THE TESTED SUBSTRUCTURE IN PSEUDODYNAMIC TEST

摘要

Aiming at the influence of the tested substructure in the steel-frame pseudodynamic test, substructure pseudodynamic tests were carried out on a six-story building with the tested substructure in the form of a single-degree of freedom (SDOF) system and a multi- degree of freedom (MDOF) system, i. e., a single- story substructure and a two-story substructure respectively. The substructure pseudodynamic tests were implemented on a two-story steel frame with 1/3 scale by using MTS computer-actuator on-line system. The testing results were analyzed from the aspects of story displacement, base shearing force and story relative acceleration. The investigated results indicate that the influence of the number of freedom degree of the tested substructure on the entire structural responses is small, as the results obtained by adopting the SDOF tested substructure are mostly coincident with the MDOF. Therefore, in substructure pseudodynamic tests the computer simulation on elastic stories almost has no effect on the seismic responses of the entire structure. Furthermore, regardless of the SDOF or the MDOF tested substructure, the seismic responses of the entire structure under the earthquake wave can be obtained accurately, given that the elastoplastic responses may only occur at the bottom story.