The comparison of empirical and finite element methods to evaluate soil foundation capacities for coastal dike

Abstract

There are over 6,300km of coastlines in the North Maluku province of Indonesia due to tidal waves which originate from the pacific ocean. The waves deposit finely loosed materials and light soil formations on coastlines, therefore causing abrasion. A common example occurred in Toseho, Tidore, and Archipelago districts. Moreover, the local residence has been faced with this challenge for up to thirty years. For this reason, deliberations to construct a dike became significant, although, the soil properties are vulnerable. This reasearch, therefore, compares the empirical calculation to the finite element method (FEM) to ascertain soil foundation capacities. The results showed the safety factor, Fs, for dike height, Hd, of 3.5 m and width bottom, B1, of 12.5m appeared below 2.0 for soil friction φs of 10∼ 15°, while estimates above 2.0 depicts soil friction φs of 20°. Furthermore, the soil stresses beneath the dike were determined empirically at qmax of 5.97 t/m2 and σs of 4.57 t/m2, while FEM evaluated the deformation elastic at 12.5 cm.