ABSTRACT

Physical modeling and numerical simulation are the main methods to study the overall stability of high arch dams and have been widely used. However, further investigation is required for assessing the overall stability of high arch dams based on a comprehensive method, which combines overloading and strength reduction in one model, and can simulate the water pressure overloading on the dam upstream face and the strength reductions of weak structural planes simultaneously. In this paper, first, based on the comprehensive method, the evaluation basis for the safety factor of the arch dam stability is established. Then, combined with practical engineering, three-dimensional (3D) geo-mechanical model test and 3D nonlinear Finite Element (FE) analyses are adopted to study the overall stability of Jinping I high arch dam. The deformation characteristics, failure patterns and mechanisms of the arch dam, the dam abutment and foundation during loading are obtained through the comprehensive method. The safety factor for the overall stability of the dam is found as 5.2∼6.0 by the comprehensive model test and 5.98 by the comprehensive FE computation. The overall stability of the Jinping I high arch dam under the condition of reinforced foundation is evaluated comprehensively by combining the results of the two methods. The research results provide an important scientific basis for safe operation of the project.