Two- and three-dimensional dynamic finite element analyses of the Long Valley Dam

Earthquake response records from the well-instrumented Long Valley Dam in the Mammoth Lake area of California are compared with numerical prediction made using finite element models. The soil response to cyclic loading is accounted for by the use of a multi-surface plasticity model. The input and output to the finite element analyses take the form of accelerations at the base and at various crest locations. The computed and measured crest acceleration are compared in both the time and frequency domains. Natural frequencies have also been obtained for the finite element models and for the real structure. The time-domain results give good agreement and high correlation in the up/down-stream direction but poor agreement in the vertical direction. The failure of the finite element models to capture the high-frequencies present in the vertical and transverse directions is thought to be partly due to the crude finite element discretization used.