Research on dynamic response characteristics and control effect of mega-sub controlled structural system under long-period ground motions

Abstract

New structure system, named as Mega-Sub Controlled Structure System (MSCSS) is proposed after the combination of structural response control theory and the construction principle of megastructures. This newly proposed structure, MSCSS, is based on a new structural response control mechanism and has a significant response control effect. The response control effect of the structure under long-period ground motions is studied in this work. Firstly, Hilbert-Huang transform (HHT) is employed to analyze the time–frequency power spectral density characteristics of three typical ground motions, and their spectrum distribution is discussed. Under long- period ground motions, Single-Degree-of-Freedom system showed different trend in its response spectrum. Subsequently, a reasonable cross-section was designed for MSCSS and a finite element model was established using SAP2000 and ABAQUS software respectively and the accuracy of the MSCSS finite element model was verified. Three structural response control indexes are defined and the response control characteristics of MSCSS under long-period ground motion are explored. The results show that the response control rate of MSCSS under the action of long-period ground motions is above 10%, and the control rate of base shear force is about 20%, which reflects the good energy dissipation effect of MSCSS. In addition, this study provides a basis for the dynamic matching design between the mega-structure and substructure of MSCSS.