The effect of core shape on the seismic behavior of earth-fill dams

Abstract

The two-dimensional study of the seismic behavior during an earthquake and earthquake resistant designs of earth fill dams usually are studied by assuming plane-strain problems. For a given earthquake loading, the results of the dynamic analysis depend on many parameters of which the core shape contributes more. The present study is concerned analysis of the seismic response of earth dams affected by different core shapes. In addition to the material properties and the shape of the dam body, foundation and abutments, the core shapes can amplify or attenuate the input earthquake loading during seismic analysis of earth fill dams. This paper evaluated the influence of core shape on behavior of earth fill dams during earthquake. All sections are described using the simple and popular non associated Mohr-Coulomb criterion. Results reported in this paper represent 3D numerical parametric study of an earth fill dams subjected to earthquake loading and 3D effects on its seismic performance. Emphasis is put on the effects of the core shape on vertical stress, pore water pressure and settlements. Also, the arching ratio and the acceleration response are taken into account during analysis. The assumed 3D model is simulated in finite difference numerical code, FLAC3D. Results regarding the importance of the core shape on the seismic response of earth fill dams show that in different sections of dams by increasing the core slope, pore water pressure increases. On the other hand, dam's settlement is affected by the core shape. In fact, by increasing the core slope, the settlement decreases. Also, the core shape have little effect on vertical stress and arching.