Control Characteristics of Mega-sub Controlled Structure System with Friction Damper under Rare Earthquake

In this paper, the seismic responses control characteristics of Mega-structure, Mega-sub Controlled Structure System (MSCSS) without dampers and MSCSS inserted friction dampers are investigated respectively under rare earthquake by using the elastic-plastic time history analysis method. The distribution of plastic hinges and different control efficiency of these structures under rare earthquake are demonstrated comprehensively. The results show that the control efficiency will be best when friction dampers are installed in bottom five-storey of second and third sub-structure. Under rare earthquake, both the Mega-structure and MSCSS are not destroyed,but the number of plastic hinges appearing in the former are more than in the latter. Under super rare earthquake, for example, as the maximum peak value of seismic acceleration reaches 1000 gal, the Mega-structure is destroyed, but the MSCSS without dampers still has certain bearing capacity, in which there are some plastic hinges appearing; the MSCSS inserted friction dampers only has a few plastic hinges, it has stronger bearing capacity than the other two structures, and more important, the responses control efficiency of this structure is still obvious. It is demonstrated in the paper that friction dampers can improve the control capacity of MSCSS and has good control characteristic, they also can effectively reduce the displacement and acceleration responses of sub-structures. Keywords—Mega-sub Controlled Structure System, friction dampers, rare earthquake, control characteristics Manuscript received October 14th, 2010; revised November 16th, 2010. This work was supported in part by the Ph. D. Programs Foundation of Ministry of Education of China (Grant No. 20096102110018) Tao Li is a doctor student in College of Mechanics and Civil Engineering, Northwestern Polytechnical University, Xi’an Shaanxi, CO 7100129 China ( phone: 0086-18991849458; e-mail: [email protected]). Xun’an Zhang is a supervisor in College of Mechanics and Civil Engineering, Northwestern Polytechnical University, Xi’an Shaanxi , CO 7100129, China ( e-mail: [email protected]). Qian’qian Wang is a postgraduate in College of Mechanics and Civil Engineering, Northwestern Polytechnical University, Xi’an Shaanxi , CO 7100129, China. . INTRODUCTION I In order to reduce the responses of tall buildings under external forces such as earthquakes and winds, the passive control method is used pervasively. Tuned mass damper system and damper devices are applied to some tall buildings for altering the dynamic characteristics of the structures under external loads. mega frame