带黏弹性阻尼器支撑木框架结构抗震性能研究

Study on seismic performance of timber frame structures with visco-elastic damper braces

为研究黏弹性阻尼器支撑对木框架结构抗震性能的影响,设计并制作了板式黏弹性阻尼器和带黏弹性阻尼器支撑的一榀木框架结构缩尺模型,并对该木框架进行了拟动力试验。研究了板式黏弹性阻尼器的耗能特性,同时还研究了带黏弹性阻尼器支撑一榀木框架在地震作用下的位移响应、恢复力-位移曲线和结构刚度退化。结果表明:该板式黏弹性阻尼器具有较好的耗能特性;木框架在8度罕遇地震作用下的层间位移角最大值为1/43,满足木结构弹塑性层间位移角限值1/30的要求;试验过程中带黏弹性阻尼器支撑的木框架力-位移曲线较饱满,黏弹性阻尼支撑耗散了大部分的地震能量,有效提高了木框架结构的抗震能力;木框架的结构刚度在试验过程中随着损伤的累积不断下降,但最终趋于平稳。

In order to investigate the effect of visco-elastic damper braces on the seismic performance of the timber frame, the visco-elastic damper and reduced-scale single timber frame connected with visco-elastic damper were de- signed and manufactured. In this study, the mechanical test of visco-elastic damper and pseudo-dynamic test of single timber frame with visco-elastic damper were conducted. The energy consumption characteristics and the skeleton curve of visco-elastic damper, the displacement response, hysteretic curve model and structural stiffness degradation of re- duced-scale single timber frame with visco-elastic damper under seismic action were investigated. The experimental re- sults showed that the visco-elastic damper under the action of constant energizing frequency with different displacement amplitudes had high dissipation capacity, which proved by the parameters of apparent storage shear module, dissipa- tion factor and dynamical loss shear modulus. The maximum story drift angle of the frame under the rare earthquake of 8-degree intensity was 1/43, which met the requirement of elastic-plastic story drift limited value of 1/30 for timber structure, moreover, the ultimate sheafing deformation value of visco-elastic damper was 192.4%, which strongly proved that the visco-elastic polymer material was in a plastic state and absorbed part of the seismic energy. The hys- teretic curves of the frame with visco-elastic damper were plump, and visco-elastic damper dissipated most of the seis- mic energy, which improved the seismic performance of the timber frame. The structure stiffness of frame was de- scribed by the parameter of secant stiffness, which declined constantly with the cumulative injury during the whole test process and tended to smooth eventually. Ultimately, the single timber frame with visco-elastic damper met the seismic requirements of ＂No damage under minor earthquake, repairable damage under moderate earthquake, no collapse under large earthquake＂.