云南省博物馆新馆隔震结构模拟地震振动台试验研究

Shaking table model test of New Yunnan Provincial Museum

云南省博物馆新馆是采用基础隔震结构的大型建筑,其隔震层采用铅芯橡胶支座与橡胶支座。该结构为钢-混凝土混合结构,具有楼板不连续、竖向杆件不连续等特点,并且屋面钢桁架设有多层钢结构悬挂层。为研究该隔震结构的抗震性能,进行了1/30比例模型模拟地震振动台试验。结果表明,8度多遇、设防和罕遇地震作用下结构未出现破坏,结构自振频率未有明显变化,结构保持为弹性状态;在多遇、设防和罕遇地震作用下主体结构加速度放大系数小于1,设防烈度地震作用下,层间位移角小于弹性层间位移角限值;隔震层支座滞回曲线饱满,具有良好的耗能能力;结构在不同地震波作用下的加速度和位移反应不同。结构4～6层测点加速度放大系数和层间位移(角)略大,模型顶部钢桁架系统隔震效果不明显。

The New Yunnan Provincial Museum is a large isolation building,where the LRB and RB bearings are used at the isolation story.Steel-concrete hybrid superstructure of the building has the following features.Some floors are discontinuous.Lots of vertical members are not straight.The steel truss on the roof has three suspended stories and so on.In order to investigate the seismic behavior of the isolation structure and to help improve the design,the 1/30 scale shaking table model test was conducted.After experiencing 8 degree frequent earthquake,design earthquake and rare earthquake,the building model doesn＇t fail and the natural frequency of vibration doesn＇t change.The structure is still in elastic range.When experiencing different earthquake waves,the amplification coefficient of acceleration（Ka） of the model is less than 1.The structure can meet the elastic story displacement ratio（θe） limit when experiencing design earthquakes.The isolated bearings exhibit full hysteretic curves and good energy dissipation.The structural acceleration and displacement are different under different earthquake waves.But under some conditions,Ka and θ on stories 4-6 are a little high.The steel truss model on the roof has no effective seismic mitigation effect.