模拟拱坝坝体-库水相互作用的振动台动力模型试验研究

A Shaking Table Dynamic Model Test on Simulated Arch Dam-Reservoir Interaction

采用仿真混凝土材料在振动台上进行逐级加载的拱坝坝体-库水相互作用的动力模型试验研究,分析拱坝从弹性阶段到破坏阶段的动力响应和损伤情况。在不同的地震波激励下,测得拱坝沿不同高程拱圈和拱冠梁的坝面动水压力分布,拱冠梁处动水压力最大值在坝底至距坝底1/3坝高之间,认为拱坝动水压力分布与坝体体型、山体形状、地震动强度、地震干扰频率和地震激励方向等因素有关。在人工波顺河向激励下,通过坝体基频、加速度响应分析确定坝体在0.377 g时出现损伤,0.471 g时在坝体两侧靠近坝肩和距右岸1/4拱圈处率先出现贯穿裂缝,确定了坝体抗震薄弱部位,对研究坝体的抗震安全有重要意义。

The dynamic model test of arch dam-reservoir interaction with step-by-step loading of simulation concrete material on shaking table is carried out.The dynamic response and damage of arch dam from elastic stage to failure stage are analyzed.Based on different seismic wave excitations,the distribution of hydrodynamic pressure along the arch ring and crown cantilever of the arch dam was measured.The maximum hydrodynamic pressure at the crown cantilever is between the bottom of the dam and 1/3 dam height at the bottom of the dam.The hydrodynamic pressure distribution of the arch dam was considered to be related to the shape of the dam body,the shape of the mountain,the intensity of seismic,vibration frequency,and direction of earthquake excitation.In the artificial seismic wave along the river,the damage of the dam body in 0.377 gis determined through the analysis of the fundamental frequency and acceleration response of the dam.At 0.471 g,penetrating cracks first appeared on both sides of the dam near the dam abutment and 1/4 arch ring,and the position of damage of the dam was determined,which was of great significance for the study of the seismic safety of the dam.