A generalized Kelvin solution based method for analyzing elastic fields in heterogeneous rocks due to reservoir water impoundment

This paper develops an analytical method for assessing the additional elastic fields in the heterogeneous rocks beneath a reservoir due to its water weight loading. The proposed method is based on the fundamental solution of layered elastic solids and integrates numerically it over the loading areas. It can deal with arbitrarily depth-heterogeneous rock solids and complex surface loads. Specifically, the method is applied to the analysis of the stress increases in the rock strata due to the impoundment of water in the Zipingpu reservoir. Nearby the reservoir, the epicenter of the 2008 Wenchuan earthquake was located. The surface contours of the Zipingpu reservoir from the Google map are utilized to obtain the reservoir topography. It is assumed that the water loads act on the projection surface of the water level of the reservoir on the horizontal plane of the dam foundation. The projection surface is discretized into the element mesh and used to generate the reservoir topography and the water loading on the layered rock surface. The proposed method is used to calculate the additional elastic fields in the neighbourhood of the epicenter and beneath the dam.

► A new method is developed for assessing the elastic fields by the water load of a reservoir. ► The heterogeneous rocks in depth can be represented by a layered elastic system. ► The projection area of the water level of the reservoir is discretized. ► The elastic fields for different areas below the Zipingpu reservoir are analyzed.