基于层间位移利用率法修正消能减震结构的附加阻尼

Correction additional damping of an energy-dissipation structure based on a story drifts utilization ratio method

详细分析了悬臂墙式黏滞阻尼器层间位移利用率(阻尼器位移与楼层位移之比)中阻尼器位移的三个组成部分,即楼层位移、梁柱节点转动、悬臂墙自身变形所引起的阻尼器位移。推导了层间位移利用率与阻尼器布置位置和消能子结构梁柱刚度比两个参数之间的关系,并采用与这两个参数相关的修正函数来考虑仿真模拟中较为繁琐的阻尼器动刚度问题,得到实用的层间位移利用率计算公式。研究结果表明:层间位移利用率在阻尼器靠边布置时小于1,居中布置时大于1,且布置越接近梁跨中层间位移利用率越大;随着消能子结构梁柱刚度比的增大,层间位移利用率在阻尼器靠边布置时增加,居中布置时减小,即都更接近于1;层间位移利用率越大,达到同样期望附加阻尼比所需的附加阻尼越小,体现出更好的经济性。最后,通过工程实例充分地验证了该减震设计方法的正确性与实用性。

Three components of story drifts utilization ratio were analyzed in a cantilever wall viscous damper, namely by story lateral displacement, beam-column joints rotate and cantilever wall deformation itself caused. The relationships between story drifts utilization ratio and damper arrangement position, the stiffness ratio for beam and column of the energy dissipation substructure were derived. The correction function associated with above two parameters to consider the simulation problem of more complicated dynamic stiffness of the damper was used. Practical story drifts utilization ratio formula for calculation was obtained. The results show that ： the story drifts utilization ratio is less than 1 when the damper is placed on the edge, is greater than 1 when the damper is placed in the middle. The value of the story drifts utilization ratio was increased with the damper arrangement closer the middle of beam. And the story drifts utilization ratio was closer to 1 with the stiffness ratio for beam and column of the energy dissipation substructure increased, which was increased when the damper arrangement close to the edge, and decreased when placed in the middle. The larger story drifts utilization ratio, the smaller additional damping need for achieving the same desired additional damping ratio, and the better economy gains. Finally, the project examples show the correctness and practicability of the energy dissipation design method.