عنوان مقاله [English]
Considering the important and vital role of dams in the industry and economy of countries and the catastrophic nature of their possible failure, the safety of these huge structures is of special importance. Arched, Karun 4 double arched concrete dam has been selected as a case study. ABAQUS 6.12 finite element software was used for numerical analysis of Karun 4 dam. In this research, three numerical models were modeled and analyzed so that in the linear model, the dam body was completely integrated and homogeneous, and in two nonlinear models, the contraction joints in the dam body with two different and widely used types were considered. The results show that the lack of injection of the joint has caused a significant increase in the maximum stresses upstream of the dam so that most of the upstream of the dam, which was initially working under pressure, has been stretched. Tensile stresses in the upstream support and downstream canopy of the dam have also increased. On the other hand, the amount of vertical compressive stresses between the contact surfaces in the absence of seam injection has increased significantly that these stresses in the vicinity of the injection stop level has almost doubled to the original level. Blocks zero and one, the maximum of which in full injection is 13.5 MPa, has increased to 11.3 MPa at this point without injection. The results show that by increasing the joint thickness and if the joint is not injected, the values of maximum stresses, minimum stresses, barrier displacements and vertical compressive force between the contact surfaces are significantly increased.