Stability analysis of Bakhtiary concrete arch dam abutments using upper bound theorem

Today, large dams are constructed with the different purposes of hydroelectric energy production, tourist attraction, increasing downstream life dams, etc. Concrete arch dams are one of the most affordable large-scale dam construction methods. Much of the reservoir pressure are supported by the abutments in concrete arch dams. This, in turn, highlights the significance of the stability of concrete arch dam abutment. Traditional method of abutment stability analysis calculates the safety factor of potentially slipping wedges using limit equilibrium. In this method rock wedges are considered rigid with no internal discontinuity. In this research, after a short review of geological structure of Bakhtiary dam site and recognition of potential slip wedge, the load distribution of abutments are estimated using finite element method. In numerical modeling, a least simplification in dam body and abutment geometry is purposed. Infinite elements are used to reduce effect of boundary condition. Finally, stability of Bakhtiary arch dam abutments slip wedges has been approved by the application of upper bound theorem. Despite the limit equilibrium method, the proposed method is based on energy-work balances and is able to account for the effect of internal discontinuities yield.