Abstract: Wudongde hydropower station is the upper cascade of the four cascaded hydropower stations on the Jinsha River lower reaches. The dam is 265 m high double curvature arch dam. Based on nonlinear finite element method, the dam and foundation were considered as a system together to analyze. The contraction joints, radiation damping of infinite foundation and nonlinear behavior of the slide surfaces in abutment wedges were all taken into account. The aseismic safety of strength of dam body and stability of abutment wedges were studied under the design earthquake and check earthquake. The ultimate aseismic capacity of the dam-foundation system was explored as well. The results show that, in the design earthquake, only the tensile stress of the arch end areas exceeds the tensile strength, while the compressive strength is all within the strength, and the abutment wedges are stable; the stress increases a little in the check earthquake and the dam-foundation system won’t break under the check earthquake; with the inflection points in the displacement or deformation curves of the typical points as evaluation criterion, the seismic overloading safety factor of the dam-foundation system can be taken as 2.7; while the corresponding horizontal peak acceleration is 0.729g; and the strength reserve safety coefficient can be taken as 2.0 conservatively, which proves that the Wudongde high arch dam owes strong ultimate aseismic capacity.

Key words: Wudongde hydropower station, high arch dam, ultimate aseismic capacity, nonlinear finite element method