Cracking Behavior of a Concrete Arch Dam with Weak Upper Abutment

Abstract

The cracking behavior and failure mode of a 78 m high concrete double-curvature arch dam with weak upper abutment are investigated through performing cracking analysis. The mechanical behavior of concrete is simulated using a smeared crack model, in which a combination of the compression yield surface and the crack detection surface with a damaged elasticity concept is employed to describe the failure of concrete. The arch dam with practical mechanical properties of the upper and lower abutments is firstly studied with emphasis on its cracking behavior during overloading. Then, a comprehensive sensitivity analysis is carried out to investigate the influence of the ratio of the mechanical properties of upper abutment to those of lower abutment on dam failure with prime attention placed on the failure mode. Simulation results indicate the adopted smeared crack model is well-suited to the crack analysis of concrete arch dam. It is shown that cracking is localized around the interface between upper and lower abutments, which leads to a fast crack growth in the through-thickness direction of dam and finally causes the dam failure. Furthermore, the sensitivity analysis presents three types of failure modes corresponding to different ratio value, wherein Modes II and III should be avoided since the weak upper abutment plays a predominant role in the cracking and failure of concrete arch dam.

Comparisons of Tensile Fracturing Behaviors of Hydraulic Fully Graded and Wet‐Screened Concretes: A Mesoscale Study

“…where ϵ is the parameter de ning the rate at which the function approaches the asymptote; σ t0 is the uniaxial tensile stress at failure; ψ is the dilation angle measured in the p − q plane at high con ning pressure. As stated earlier, the material softening under tension is de ned by the relationship between the uniaxial tensile e ective strength and equivalent tensile plastic strain (5), which means mesh sensitivity will be encountered when applying the CDP model in FE simulations. erefore, a stress-displacement relation is used in this study to de ne the tensile softening behavior for alleviating the in uence of mesh sensitivity on the simulation results.…”

“…As a result, the mechanical behaviors of HFGC are different from those of the extensively studied ordinary concrete [3]. us, to obtain the fundamental mechanical parameters especially the parameters related to fracturing behaviors, which are needed by the failure analysis of hydraulic mass concrete structures, a detailed investigation on the mechanical behaviors of HFGC is required [4,5].…”