多塔大底盘层间隔震与基础隔震高层建筑抗震韧性对比

SEISMIC RESILIENCE COMPARISON BETWEEN TALL BUILDING WITH ISOLATED INTER-STOREY MULTI-TOWER BASE AND ONE WITH AN ISOLATED LARGE CHASSIS

建设层间隔震地铁上盖建筑已成为高烈度地区实现以公共交通为导向建设集约紧凑型城市的重要手段,同时面对韧性城市的建设需求,提升该类建筑的抗震韧性已成为土木领域研究热点。该类建筑中大底盘对隔震结构地震响应和抗震韧性的影响,塔楼与大底盘抗震韧性的差异性、两者对建筑整体抗震韧性的影响等关键问题有待研究。屈重比作为隔震结构设计关键指标,其对多塔大底盘层间隔震建筑的抗震韧性的影响规律有待明确。该文以5个屈重比取值分别设计了多塔大底盘层间隔震案例和基础隔震案例,开展了弹塑性时程分析和抗震韧性评价。结果表明:大底盘对层间隔震建筑的地震响应存在放大效应,进而导致层间隔震建筑韧性等级低于基础隔震建筑。塔楼和大底盘的修复费用和时间构成存在差异,塔楼的修复费用和时间由加速度敏感型非结构构件引起,而大底盘的修复费用和时间由结构构件和加速度敏感型非结构构件共同引起。多塔大底盘层间隔震建筑的整体韧性等级随屈重比降低而提升,但屈重比对塔楼和大底盘的抗震韧性影响规律存在差异,塔楼的修复时间和费用随屈重比的降低逐渐减小,而大底盘的修复时间和费用随屈重比的降低无明显变化。

The construction of inter-storey isolated buildings on the top of metro depots is an important method to achieve the demand of transit-oriented development of compact city.The seismic resilience improvement of such type of building has become a popular topic due to the demand of construction of resilient city.Critical issues to be investigated are the influence of the large chassis on the seismic responses and seismic resilience of the isolated structure,the difference between the seismic resilience of the tower and the large chassis,and the influence of tower and large chassis on the seismic resilience of the overall building.The influence of yield ratio on the seismic resilience of such type of buildings is needed to be clarified.In this study,inter-storey isolated multi-tower tall buildings with a large chassis and base isolated tall buildings were designed upon five yield ratios,then nonlinear time-history analysis and seismic resilience assessment are carried out.The results indicate that amplification effect on the seismic responses of inter-story isolated building is observed because of the large chassis,leading to the seismic resilience of inter-story isolated buildings lower than that of base isolated buildings.The composition of repair cost and time are different for the tower and large chassis,the repair cost and time of the tower is mainly caused by acceleration-sensitive non-structural components(ASNSCs),while the repair cost and time of the large chassis is mainly caused by the combination of structural components and ASNSCs.The seismic resilience level of inter-storey isolated buildings increases with decreasing yield ratio,but the effect of yield ratio on the seismic resilience of tower and large chassis are different.The repair cost and time of tower gradually decreasing with the decrease of yield ratio,while the repair cost and time of large chassis was not affected by the variation of yield ratio.