STABILITY EVALUATION OF SMALL CONCRETE GRAVITY DAMS

Abstract

The aim of this work is to ensure the structural stability of small concrete gravity dams by selecting the economic practical section that reduces the material’s costs with the least acceptable factors of safety. The main parameters associated with the geometric shape; or the slope of the base of the dam, material properties (cohesion and angle of friction), the presence of passive wedge, as well as the conditions of loading with normal and maximum water heights of 30m and 33.6m, respectively, in addition to extreme condition with earthquake forces; will be the parameters presented to evaluate the structural stability for concrete gravity dams. The study of stability criteria was done on twelve virtual dam cases according to two standard methods U.S Bureau of Reclamation (USBR) and U.S Army Corps of Engineers (USACE), to obtain the height of water for safe operation and the strength of concrete required to avoid overturning and sliding of the dam. The behavior of the dam has been modeled and analyzed using an analytically 2-dimensional gravity method and FEM by using the ABAQUS software package in order to ensure the safe performance of the dam. Stresses were found acceptable in all profiles, where it is important to prevent undesirable tensile stresses at the heel and to avoid crushing at the toe. The profile DAM 2B with a base inclined by 6.75o upwards toward the downstream face, and width b= 25.35m was found the most optimum section for a dam required to store a volume...