EFFECT OF CREST SHAPE ON THE STRUCTURAL PERFORMANCE OF THE DOUBLE CURVATURE CONCRETE DAM

Abstract

Arch dam stability is one of the main engineering challenges that must be met in the early stages of investigations and design of the dam. The highest degree of stability can be achieved if the dam’s structure formed in best layouts and the free ends of the dam body, defined by the crest, restricts especially if the dam is affected seismically. This research study falls under the auspices of the second phase of concrete dam construction, i.e. design stage. Nonlinear finite element analysis is performed in order to investigate the structural behaviors of the four models of double curvature concrete arch dam. Three-dimensional models of arch dams are prepared to utilizing Revit, the building information modeling software. Subsequently, the four models are linked to the finite element’s tools package of Abaqus 6.13 for the purposes of discretization and structural analyses. The models have the same mechanical properties and basic dimensions and differ only in the form and physical appearance of a crest (crest shape). Amplified of crest shape caused a slight movement of the dam center of the mass to be optimally positioned, and thus the new center of mass supports the stability of the dam. The varying effects of crest configurations on the whole dam structure response were discovered according to the results of maximum and minimum principal stresses along the crown cantilever path as well as to the displacements response along the crest path of the arch dam. Strengthening or amplified crest dimensions could decrease arch dam thickness for a certain value and can reduce the response of the displacement to about 30 percent. The results indicated a reduction in the undesired movement between the adjacent cantilevers at the contraction joint zone, so a marvelous response was remarked in both of triangle upward edges crest and triangle downward edges crest models.