基于大底盘多塔楼的集中质量模型,考虑了基础隔震和层间隔震体系隔震机理的差异,推导了大底盘多塔楼层间隔震结构计算简化模型的运动方程,并对某实际工程进行了参数分析和计算仿真.结果表明:大底盘多塔楼层间隔震结构其隔震层参数对隔震效果影响显著,当隔震层刚度减小时,有利于上部结构剪力控制,但可能增加大平台层间剪力;增大隔震层阻尼对下部结构有较好的减震效果,而对于上部塔楼则存在阻尼最优值.针对大底盘多塔楼结构提出3种隔震减震策略,文章采用5条地震波对某实际工程结构进行了3个方案计算仿真分析,并比较了3种隔震方案的减震效果.
Based on lumped mass model of multi-tower structures with a large podium, this paper establishes the equation of motion of the newly isolated structure system. The parameter analysis of the isolation system is investigated and studied in detail. It is found that the isolation parameters of the isolated tower with a podium have a great influence on the control effectiveness. Results show that less stiffness of isolation layer will lead to a reduction in base shear of the platform while probably increasing shears of the isolated towers. With increasing damping level, the seismic responses of the podium remain decreasing. For the isolated tower, there is always an optimal damping level. Three isolation strategies for multi-tower structure with a large podium system are proposed herein, each of which is corresponding to a different design idea. A practical engineering structure is used as a numerical example, and three isolation strategies are simulated and compared systematically for a series of earthquake records. Some useful conclusions are obtained and will be helpful for future design of this complex structure system.