沥青混凝土心墙坝心墙与基座模型抗震试验研究

Seismic test study of core wall and base model of asphalt concrete core wall dam

沥青混凝土心墙坝心墙与基座的连接型式对坝体防渗性能有着重要影响.针对沥青混凝土心墙坝心墙与基座的两种不同接头型式(弧形和水平接头),精心设计了其他条件均相同的振动台模型类比试验,利用高速高清相机记录整个振动过程,采用PIV图像分析方法研究两种接头型式心墙与基座间的错动、心墙的倾斜以及接头处防渗性能的差别.采用动力有限元法对物理模型进行数值模拟,并与物理模型试验结果进行印证.结果表明:弧形接头沥青玛蹄脂层的错动比水平接头的小,而心墙倾斜度比水平接头的稍大;随着沥青玛蹄脂层厚度的增加和心墙两侧压力差的增加,错动和倾斜逐渐增大.数值模拟分析与物理模型试验结果定性上一致.

The type of joint between core wall and base has a major impact on the anti-seepage behavior of asphalt concrete core wall dam. The analogical shaking table model tests about two different joints （arc-shaped and horizontal joints） are designed while other things are equal. High speed and high definition camera is used to record the whole vibration process, which is further used to study the dislocation between asphalt concrete core wall and base, the tilt of core wall and the anti- seepage behavior of joints through PIV image analysis method. A dynamic finite element method is applied to simulation of the physical model, and its numerical results are compared with the actual responses of test model. The research results show that the asphalt mastic layer dislocation of arc- shaped joint is smaller than that of the horizontal joint, but the tilt of arc-shaped joint is slightly larger than that of the horizontal joint; and both of the two quantities will be larger with the increase of the thickness of asphalt mastic layer and the difference of pressure on both sides of the core wall. In addition, the results of numerical analyses are qualitatively consistent with those of model test.