Three-Dimensional Modal Analysis of Brezina Concrete Arch Dam, Algeria

In this paper, modal responses of the Brezina concrete arch dam, Algeria, are determined using the finite elements commercial packages ANSYS. To study the effects of the foundation soil, three 3D models have been created, the dam alone without soil, the dam-massless soil and the dam-soil with soil mass model. Moreover, a parametric study of the viscous damping, in Raleigh form, has been conducted. It is found that the natural frequencies of either undamped or damped modes obtained from the dam-soil with soil mass model are drastically lower compared to that of the dam alone model, and are markedly lower than those obtained from the dam-massless soil model. Likewise, similar comparisons have been observed for the damping quantities, in absolute values, between the three models. An in-depth review of the literature reveals that the study carried out herein constitutes several elements of originality as only very few similar work have been undertaken.