Experimental and numerical study of cracking behavior of openings in concrete dams

Openings for waterways, such as spillways, outlets and penstocks are usually incorporated within concrete dams. The concentration of tensile stresses around the opening due to applied stresses tends to localization of cracks around this region which results in significant reduction of strength and escape of water into the interior of dam. This influence should be diminished by consideration of appropriate reinforcing bars in these regions that can be determined by accurate nonlinear analysis procedure and appropriate material models. Cracking response and failure behavior of reinforced concrete outlets in concrete dams are experimentally observed through testing a large-scale model of deep outlet of TGP dam in China. The deficiencies of existing constitutive models and design procedures are pointed out and the finite element simulation of cracking response of such a structure is presented.