Numerical modeling of grouted connection damage development under uniaxial loading

Abstract

The grouted connection (GC) is exposed to harsh load condition, and the mechanical properties of the grout are of importance to the ultimate bearing capacity of the GC. Grout cube specimens were tested for their ultimate capacity, and five GCs were tested with variable radial-stiffness. The test specimens were numerically modeled and validated regarding the load–displacement behaviors. Additionally, variable shear-key height to spacing ratio (h/s) was investigated by the finite element method (FEM). The scalar degradation (SDEG) parameter was used to estimate the regional average damage (RAD) and the damage index (Dv). The capacity of the GC increased with increasing radial-stiffness for both experiment and the FEM. The RAD and Dv increased with increasing h/s at post-peak load. From the parametric studies on actual size GC, the ultimate capacity increased with increasing h/s, diameter of GC, and grout-length. For the design-load within the elastic-limit range, when h/s was increased from 0.05 to 0.06, the top and bottom RAD reduced by 50% and 31% and the displacement by 39% respectively. The damage development can be used as a tool for knowing the behavior of the actual-size GC.