Dynamics of earth dams under shock impacts

Abstract

The article provides a detailed analysis of well-known studies, which allow considering the work of the structure together with the base under dynamic influences, adequate replacement of an infinite base with a finite one using non-reflecting conditions on the boundary of the finite region, well-known methods for assessing the behavior of a structure under impact. A mathematical model, method, and algorithm were developed to evaluate the dynamic behavior of earth dams together with the base under shock impact using non-reflective conditions based on Rayleigh waves on the boundaries of the finite area of the base. To simulate a dynamic process, the principle of virtual displacements is used, taking into account the viscoelastic properties of the material. The solution to the problem is conducted by the finite element method and the Newmark method. The dynamic behavior of earth dams, together with the base, is studied, considering non-reflecting conditions under explosive impacts that arise not far from the structure. It was established that during the period of wave travel, a non-synchronous movement of individual parts of the dam occurs, damped due to the wave entrainment of energy and the viscoelastic properties of the material. It was revealed that the maximum principal stresses σ1 occur in the lower part of the upper slope of the dam and gradually spread along the entire dam; the maximum principal stresses σ2 are reached near the foot of the dam and, as the wave propagates, they move along the base directly behind the wavefront; the maximum values of shear stress σ12 are reached on the surface of the upper slope, first at the foot of the dam, then over the entire surface of the slope.