Abstract: The causes of the upper diagonal cracks at the downstream side of the main dam pier of Lushui Hydropower Complex are analyzed using finite element method with ABAQUS. By establishing a 3D model of the downstream side of the main dam 5^# pier, including the spillway surface, the pier and the foundation of hoist bents on the pier, the thermal stress was analyzed using ABAQUS. The action of solar temperature is a major cause of the cracks. In addition, a crack treatment scheme for the pier was developed, and emergency measures such as prestressed anchoring, planting reinforcement, and chemical grouting were adopted to effectively control the cracks. The research offers a reference for the treatment of similar engineering defects.

Key words: pier, crack, finite element analysis, ABAQUS, prestressed anchor, Lushui Hydropower Complex