论文部分内容阅读
开展了2个具有薄弱层的3层混凝土空间板柱结构模型的地震模拟振动台试验,采用加速度峰值逐级加大的El-Centro(NS)波作为输入激励,直至薄弱层发生落层倒塌。量测了倒塌前、倒塌后模型各层的水平加速度响应,以及倒塌碰撞引发的薄弱层及其下层楼板的竖向加速度响应。模型M-2相比于模型M-1额外施加了附加配重。试验结果表明:1)随着地震损伤程度的增加,模型的扭转效应有所增大;2)倒塌前模型M-1和模型M-2的基本频率仅比初始值分别降低8.9%和4.7%,采用频率改变幅度进行结构倒塌预警可能是不现实的;3)倒塌碰撞导致模型各层的水平加速度出现短时剧烈波动,波动期间模型M-1和模型M-2各层的绝对加速度最大值介于5g~10g之间,分别为倒塌前各层绝对加速度最大值的5倍~20倍和10倍~50倍;4)倒塌碰撞引发的楼板竖向加速度高达30g~40g。
Two shaking table tests of three-layer concrete slab-column model with weak layer were carried out. The El-Centro (NS) wave with increasing acceleration peak was used as the input excitation until the weak layer collapsed. The horizontal acceleration response of each layer of the model before and after collapse and the vertical acceleration response of the weak layer and its underlying floor caused by the collapse collision were measured. Model M-2 additionally applied additional weight compared to Model M-1. The results show that: 1) the torsional effect of the model increases with the increase of earthquake damage; 2) the basic frequencies of model M-1 and model M-2 before collapse are reduced by only 8.9% and 4.7% , It may be unrealistic to use the amplitude of frequency change to predict the collapse of structures. 3) The collapse acceleration causes short-term and severe fluctuations in the horizontal acceleration of the model layers. The maximum absolute acceleration of each layer of model M-1 and model M-2 during the fluctuation Ranging from 5g to 10g, which is 5 times to 20 times and 10 times to 50 times the maximum absolute acceleration of each layer before collapse; 4) The vertical acceleration of the floor caused by the collapse collision is as high as 30g to 40g.