STUDY OF A LONG-TERM BEHAVIOR OF LARGE EARTH DAM COMBINING MONITORING AND FINITE ELEMENT ANALYSIS RESULTS

Abstract: Sensitive structures such as large earth dams require continuous and real time information on their stability, particularly when they are located in tectonically active zones. The results from automated monitoring surveys, when compared with the predicted regular behavior of the structures, give information on the effects of seismic disturbances and may trigger a warning alarm if irregular behavior exceeding a threshold value is detected. Deformations of an earth or rockfill dam start occurring during the construction of the dam. After the construction of the dam is completed, the considerable movements of the crest and the body of the dam can develop during the first filling of the reservoir. Later, the rate of deformations decreases in time, with the exception of variations associated with the periodic variations of the level of the reservoir and, in seismic zones, with the tectonic activity. The dams located in the seismically active areas are built with the material, which allow for a dam to be more adaptable to the changes of loading conditions. The deformation process can be simulated using, for example, the finite element method. Due to the uncertainty of the model parameters, careful monitoring of the dam and its surroundings are required in order to verify and enhance the model. This paper presents an analysis of long term deformations of West Dam of Diamond Valley Lake (DVL) Project in California, U.S.A. 1