拱坝是空间壳体结构,体型较为复杂,拉应力过大会导致坝肩失稳甚至溃坝。大量的工程经验表明,拱坝最大主应力常出现在坝肩处,坝肩拉应力的大小直接影响大坝的安全运行。为有效减小坝肩拉应力,采用ANSYS有限元等效应力法,建立拱坝整体有限元模型,对模型施加静水压力、泥沙压力、扬压力、重力、弧门推力等荷载,研究已有高拱坝工程中拱坝坝体结构设计中的加切角问题,分析拱坝在正常温升、正常温降2种运行情况下拱坝坝肩受力情况,与在同种运行情况下与不加切角拱坝作对比分析。结果表明:加切角可有效改善拱坝坝肩受力情况,降低坝肩拉应力。研究成果可为减小拱坝坝肩拉应力设计和实际施工提供参考依据。

Arch dam is a shell structure in space with complex shape. Large tensile stress would lead to instability or even failure of the arch dam. Engineering experiences show that the maximum principal stress of arch dam often appears at the abutment, and tensile stress in the abutment directly affects the safe operation of dam. In the aim of effectively reducing the tensile stress of arch dam, a concrete backfill measure for the over excavation of bank slope is proposed, and the stress conditions of dam abutment in temperature rise and drop conditions in the presence of backfill are compared with those in the absence of backfill. ANSYS the finite element equivalent stress method was employed to establish the integral finite element models of arch dam subjected to hydrostatic pressure, silt pressure, uplift pressure, gravity, thrust of radial gate and so on. Results indicate that backfill could effectively improve the force situation of abutment and reduce the tensile stress in the abutment. The results offer reference for the design and construction of reducing tensile stress in the abutment of arch dam.