Three-dimensional Finite Element Analysis of Warragamba Dam

Nowadays, the availability of powerful desktop workstation and efficient finite element modelling software, which utilise three-dimensional real time graphics, enables a real-world complex problem to be simulated. This paper reviews some of the early physical and numerical models used in the analysis of Warragamba Dam. Then, the paper will describe recent finite element modelling technique involved in the analysis of the dam. The simulations of the original dam construction as well as future dam raising were carried out. Some possible scenarios namely, foundation softening, stress redistribution due to grouting of twist joints and rock creep were investigated in order to explain the occurrence and the closure of a crack which appeared in the upstream face of the dam three years after the completion of the dam in 1960. The behaviour of the raised dam under seismic activities was also investigated. The computed results were compared with observations and reasonable agreement in terms of geostatic stresses and dam deflections was obtained. Some interesting three-dimensional cross-valley action and stress arching were observed from the computations.