Relation between cracks behavior and curvature in cracked concrete arch dam under earthquake

Abstract

Dams are considered one of the most important vital installations in different eras due to the advantages they provide on the level of life for humans and other creatures or at the environmental level, in addition to being an important source for generating clean energy, which will reach the amount of its supply of electrical energy approximately 20% of the total energy in the world. With scientific progress, the era of globalization, and the emergence of structural types of dams, it has become important to study the structural composition of these types in addition to studying the extent of the impact of the dam’s shape on its stability. The arched dam is a solid concrete dam made arched at the upstream designed to withstand the hydrostatic pressure generated by water by its curved body. Depending on the type of construction arch dam can be classified into single and double curvature. The curved shape of the dam provides great performance and resistance to stresses generated from a variety of acting forces. The crack propagation under seismic loads of concrete arch dams with existing cracks on the dam's body has very limited studies. There are no clear studies links between the relation of crack propagation and the degree of curvature in arch dams. In this investigation, two different curvature models have been developed for the earthquake analysis of cracked concrete arch dams. The extended finite element method (XFEM) was used for nonlinear analyze the stability and propagation, development of cracks in concrete arch dams. A moderate earthquake magnitude of 5.7 M effects is considered in the (XFEM) analyses. The relation between the arch curvature and crack behavior are identified. The results obtained from this investigation indicate that increasing the degree of curvature of the arch dam will increase the dam stability under earthquake ground motion as well as providing good resistance for crack propagation and tensile stresses.