An Advanced Genetic Algorithm Applied to a Rare Uplifting Earth and Rockfill Dam

A rare uplifting earth and rockfill dam case is introduced. The preliminary analysis on the formation mechanism indicates the uplift of dam body is very likely influenced by water swelling minerals in bedrock. In order to verify the swelling feature of the bedrock, a back analysis on dam surface displacement through Genetic Algorithm (GA) is carried out. Considering the discovered distribution characteristics of the bedrock expansibility, an advanced Sorting Genetic Algorithm (SGA) is proposed by adding a bubble sort procedure to maintain the relations between back analyzed parameters. The Finite Element Method (FEM) is embedded in SGA process as a single displacement calculating module. And two back analysis methods, fixed expansion distribution simulation and free GA simulation, are applied to simulate the uplift displacement of the dam body. The displacement prediction in verification dam section by adopting back analyzed parameters is later carried out to verify this method. The results demonstrate that the back analyzed vertical displacement (uplift) through both methods are in good agreement with the observed ones which verifies the reliability of the proposed method and the existence of swelling bedrock.