Thermal stress analysis of a dam wall by finite element model

Arch dams are designed for the same loads as other dams with the exception of the temperature load, which has a significant influence in arch dam design as compared to gravity dam design. In concrete arch dams, because of the particular geometry, solar radiation shares of exposed surfaces vary spatially through downstream face. In this case, three- dimensional temperature distribution analysis is unavoidable. When a transient heat transfer analysis is performed in a dam safety evaluation, it would be convenient to identify the most critical time to carry out a complete stress analysis. To investigate the seismic safety of concrete dams, it is essential to quantify the static state of stress and strain that exist at the time the earthquake occurs, which may vary significantly from winter to summer conditions. In this paper, a three dimensional finite element model implemented in ABAQUS is used for simulating the temperature behavior in operational phase of typical arch dam. Then an elastic analysis is carried out and the associated thermal stresses are calculated and combined with other static loadings (self-weight and hydrostatic) and dynamic one. For dynamic analysis, a coupled system of dam and reservoir is considered. The static loads are compared and combined with earthquake load. Results show significant thermally induced tensile stresses in the crest region and at the downstream face of the dam, which is the most vulnerable zone for seismic induced damage. At the upstream face, due to the effect of reservoir water, the thermal tensile stresses have small magnitude while dynamic stresses are excessively increased.