Structural Reliability of Dapped End Beams with Different Reinforcement Layouts under Dynamic Loading

Abstract

Reinforced concrete Dapped End Beams (DEB), also known as half-joints, are used in bridges and many other pre-cast constructions to reduce end depth and increase lateral stability. Dapped end beams are expected to experience dynamic loads when used in bridges, the available past studies on the behavior and damage assessment of DEBs are mainly for static loading. The reinforcement layouts of DEBs can influence the behavior of these shear critical members under impact loading. Better understanding of the crack propagation and failure patter of DEBs under dynamics loads is required for safe and economic design of these structural elements. A non-linear numerical transient study was conducted to investigate the dynamic performance of DEBs with different reinforcement layouts. Advanced material models capable of including strain-rate effect and material non-linearity to capture realistic behavior of DEBs were used. The simulated models in finite element package LS-DYNA were verified and used to conduct detailed parametric study to investigate the impact behavior of DEBs with different reinforcement layouts. Sensitivity of concrete compressive strength, main dapped end reinforcement and special shear reinforcement detailing on the structural reliability of DEBs were studied.