滑移摩擦隔震系统在多向地面运动作用下的试验研究

Shaking table tests of model building with sliding isolation system under multi-direction ground motions

基础隔震通常只考虑隔离水平地面运动 ,而对竖向地面运动的影响注意不够。本文进行了滑移摩擦隔震系统的振动台房屋模型试验 ,研究多向地面运动输入时上部结构反应和隔震系统的性能。试验中分别对模型输入了不同方向的地震动 ,其中包括水平单向、水平双向、水平和竖向及三向地震动输入 ,对试验结果进行了分析比较 ,结果表明竖向地震动输入对上部结构的水平地震反应有显著影响 ,同时在橡胶隔震支座中产生了竖向拉力。

There is an apparent advantage in sliding isolation system with restoring force since it is insensitive to the frequency contents of seismic excitation. This paper presents a combined isolation system which consists of frictional sliding plate bearings to dissipate the input ground energy and rubber bearings to restore the system to center after excitations. Shaking table tests on model building with the combined isolation system were conducted under multi-direction ground motion to investigate the influence of the multi-direction excitations. Experimental results were compared here. It is found that the structural response under bilateral inputs is similar to that under unilateral ground shaking, but the response increases obviously not only under triaxial components but also under one horizontal and vertical components. In addition, the vertical force on the isolators varies differently and uplift occurs in rubber bearings in the test.