上海世博会中国馆抗震分析与振动台模型试验研究

Seismic Analysis and Shaking Table Test of China Pavilion for EXPO 2010 Shanghai

2010年上海世博会中国馆建筑造型和结构体系独特,主体结构为4个钢筋混凝土筒体加组合楼盖,筒体间楼盖向上层层展开出挑,呈四棱台斗冠状。倒梯形的建筑造型使上部楼层的转动惯量增大,导致结构的第一振型为扭转振型,不满足现行高层结构设计规范的要求。为了研究该结构的抗震性能,检验和改进结构设计,利用有限元程序ANSYS对整体结构进行了抗震分析,同时又进行了比例为1/27的模拟地震振动台试验。计算结果表明,虽然中国馆的第一振型为扭转,但结构的扭转反应不大,和振动台试验结果具有较好的一致性。同时,原型分析和模型试验表明结构的损伤发展符合预期的破坏形式,能够满足预定的抗震设防目标。根据试验结果,给出了改进设计建议。

China Pavilion for Expo 2010 Shanghai is designed with peculiar style and special structural system.The main structure is composed of four concrete tubes with steel-concrete composite floors.It is designed with a shape of inverted trapezoid in elevation.The fundamental vibration mode of this structure is a torsional mode due to the special shape with greater moment of inertia in upper floor,which exceeds the limit value stipulated in Chinese code.The seismic analysis of prototype is carried out by ANSYS program to evaluate its overall seismic performance and improve the structural design.At the same time,shaking table tests of a 1/27-scale structural model are conducted.It is faund that although the first mode is torsional,the torsional responses are not so large,which agrees well with the results of shaking table tests.Both the test results and calculation results demonstrate that the designed structural system satisfies the seismic damage patterns and meets the pre-defined performance objectives.Based on the test results,suggestions for improving design are also put forward.