基于振动台缩尺模型的复杂体型建筑结构楼面加速度反应分布研究

Research on floor acceleration response distribution of complex building structure based on shaking table scale models

楼面加速度放大系数(floor acceleration amplification,FAA)能够反映结构对地面加速度的放大,而当前的规范与研究多是依赖于历史楼面记录或者有限元分析结果,在涉及复杂体型建筑结构时计算分析和实际震害结果往往存在较大差异。以整体结构缩尺模型振动台试验记录数据为基础,通过拟合分析得到各条记录下原型结构沿高度的FAA分布。基于类拟地震反应谱形状模型,得到具有一定保证率的FAA分布曲面,针对不同结构类型分别提出了相应的计算公式,相比于规范能够更好地反映出复杂体型建筑结构的FAA分布特征。定性地探索了场地卓越周期变化对该类型建筑结构FAA分布特征的影响。

The floor acceleration amplification(FAA) reflects the amplification effect of the main structure on the ground acceleration,but the current specification and research mostly rely on historical floor records or finite element analysis results.When complex building structures are involved,the results of calculation analysis and actual earthquake damage are often different.Based on the recorded data of the shaking table test of the scaled model of the integral structure,the FAA distribution of prototype structures along the height are obtained by fitting analysis.Using the shape model of quasi seismic response spectrum,the FAA distribution surface with a certain guarantee rate is obtained,and the corresponding calculation formulas for different structural types are proposed respectively.It can better reflect the FAA distribution characteristics of complex building structures compared with the specification.Finally,the influence of site predominant period change on FAA distribution characteristics of this type of building structure is qualitatively explored.