基坑水平支撑受移动荷载作用的竖向随机振动分析

上海来福士广场地处建筑物密集区，施工场地狭窄，需在施工结构的水平支撑上设置２台８８ＨＣ塔式起重机。为合理配置施工结构，进行了竖向随机振动分析。结果显示；其竖向位移最大值为３２ｍｍ，满足混凝土轨道梁的变形要求。经施工现场实测，起重机荷载作用下梁变形在２５ｍｍ以内，小于计算值，证明该分析方法安全可靠，有实用价值。

VERTICAL RANDOM VIBRATION ANALYSIS FOR A FOUNDATION PIT HORIZONTAL STRUT UNDER MOVING LOAD

The Shanghai Raffles Square is located at a highly dense building district.Naturally,the actual site there would be too narrow and very difficult for construction.It was required to have 2-88 HC tower cranes set up on the horizontal struts of the construction structures.In order to cope with their construction structures,the vertical random vibration analysis has been well implemented.As a result,it has shown that its maximum vertical displacement was 32 mm which fulfills the displacement requirement of the concrete trackbeam.On-site practice has proved that beam displacement under tower crane's moving load is within 25 mm which is smaller than the designed value.Finally,it has been fully confirmed that the vertical random vibration analysis method is reliable and practical.