Optimum Characteristic Compressive Strength for CMDs (Case study: Dasht-e-Palang Dam)

Using Cemented Material Dams (CMD) is advantageous in a prospect that it allows construction of concrete dams on almost every foundation rocks including weak ones. For a successful design of this type of dams on weak rocks, more consideration is needed. Since stresses in dam body are proportional to modulus of rock and dam body, determining an optimum compressive strength (f’c) for material of dam body (named hardfill) is a major concern. Choosing low f’c means inadequate safety factor for stresses while choosing high f’c means high cost and thermal challenges for dam body. Stresses are dependent on dam and foundation’s modulus of deformations and modulus of deformation itself depends on compressive strength of material, which in turn produces a loop that should be solved correctly in an optimum way. In this paper, a probabilistic approach to determine optimum and safe f’c is proposed. Hardfill material of Dasht-e-Palang dam is chosen as a case study and analyzed by this method to obtain an optimum compressive strength of hardfill. An applicable graph for CMD design with arbitrary height and symmetrical slopes is presented in this paper.