本文用有限元与半平面边界元耦合法计算了坝体坝基应力,又结合边界配置法求出了坝踵应力强度因子。根据混凝土V型切口复合型断裂准则确定了坝踵初裂方向,在此基础上。对裂纹沿坝基的扩展作了计算分析。结果表明,裂纹内的水压力是促使裂纹扩展的重要因素,减小或消除坝基的缝水压力将有助于坝基裂纹的稳定。 In this paper, the dam abutment stress is calculated by finite element and half-plane boundary element coupled method, and the stress intensity factor of the dam heel is calculated by the boundary collocation method. Based on the composite V-notch composite fracture criterion, the direction of the initial crack in the dam heel is determined. On this basis, The crack propagation along dam foundation is calculated and analyzed. The results show that the water pressure in the crack is an important factor to promote the crack growth. Reducing or eliminating the pressure of the water in the dam foundation will be helpful to the stability of the crack in the dam foundation.