Uplift Modeling for Fracture Mechanics Analysis of Concrete Dams

Abstract

The modeling of uplift pressures within a dam, on the foundation on which it was constructed, and on the interface between the dam and foundation is a critical aspect in the analysis of concrete gravity dams. The procedures for modeling uplift pressures are well established for the traditional hand‐calculation methods, but this is not the case for finite element (FE) analysis. In this paper, the procedures for including uplift pressures in the hand‐calculation methods, as prescribed by various government agencies, are reviewed and compared. Three separate models for including uplift pressures in a FE analysis are proposed. The use of these models is demonstrated in cracked‐base analyses of two different dam geometries with identical material properties. A linear elastic fracture mechanics criterion is used to determine the final crack length rather than the strength criterion used in the hand‐calculation methods. The results of these analyses are compared with one another and with results published elsewhere for one of the two geometries but with different material properties.