The effect of non‑uniformity in ground motions on the seismic response of arch dams

摘要

Recorded ground accelerations at various locations of Karun III Dam during November 20, 2007, were recorded by anarray of accelerometers located on the dam. In terms of amplitude and phase, these accelerations show non-uniformitiesin different elevations. In this paper, the effect of these non-uniform ground motions on the seismic response of the damtaking dam-reservoir-foundation interaction into account is investigated. The EACD-3D-2008 finite element programand ABAQUS Software are used for carrying out the seismic analyses. For this purpose, time histories of the earthquakeaccelerations are interpolated at nodal points located on the dam foundation interface. The analysis has been repeated,considering the common assumption of uniform ground motions. Comparing the results obtained from these two analysesreveals that the computed displacements in the crest due to the spatially varying excitations are in more conformitywith the recorded information. Moreover, neglecting the non-uniform nature of ground motions in the model leads tounderestimating the tensile stress values within the dam body.