洞坪双曲拱坝三维渗流及坝肩稳定分析

Analysis on 3D Seepage Field & Abutment Stability of Dongping Double-curved Arch Dam

洞坪双曲拱坝两岸坝肩天然地下水位较高,右坝肩被河道切割临空而相对单薄且存在可能滑移体。坝址区渗流特性及两岸坝肩的稳定性是工程非常关心的问题。根据洞坪坝址区水文地质条件及坝基防渗处理设计措施,运用三维有限元法对洞坪拱坝蓄水后稳定渗流场及坝体坝基整体应力场进行了计算分析;根据有限元应力结果和传统的刚体极限平衡法对两岸坝肩各结构面形成的可能滑移体进行了坝肩稳定计算。结果表明,坝肩具有足够的稳定安全度,不需要采取工程加固措施。

Considering that the right abutment of Dongping arch dam is located at a narrow massif with high ground water, the problems about reservoir leakage and dam abutment stability are concerned with. On the basis of hydrogeological condition in dam area and the design scheme of seepage control, the steady seepage field by impounded reservoir and the stress distribution in dam and foundation are calculated by 3-D FEM, the dam abutment stability is analysed by 3-D FEM and rigid-body equilibrium as well. The result shows that the dam abutment has sufficient stability, so strengthening treatment for it is unnecessary.