Structural Behavior of Novel Precast TL-5 Bridge Barriers Using Ultrahigh-Performance Fiber-Reinforced Concretes

Abstract

Experimental testing and numerical modeling were performed on novel precast TL-5 barriers subjected to centered and eccentric loadings in a quasi-static mode. The mechanical behavior of two precast barrier configurations was analyzed and compared: a hybrid barrier including a normal strength concrete (NSC) core and a ultrahigh performance fiber reinforced concrete (UHPFRC) shell with a UHPFRC barrier–slab connection, and a precast version of a cast-in-place QMT301 barrier made of NSC with a UHPFRC barrier–slab connection. Laboratory experiments on 2-m precast barriers under eccentric loading applied on 0.7 m demonstrated a shear failure in the upper portion of the hybrid and QMT barriers while the UHPFRC connection recess remained elastic, as observed in the cast-in-place solution. The longitudinal connection between precast barriers increased the maximal capacity under eccentric loading at the connected end. Numerical models were carried out on 2–6 -m precast barriers, under centered and eccentric loading, with 0.7 and 2.4 m loading lengths. Models showed the critical effects of shorter barrier length (2 m), shorter loading length (0.7), and eccentric loading as these factors significantly reduce the ultimate capacity of the precast barrier. Models validated with experiments confirmed that the load-carrying capacities of the developed precast TL-5 hybrid and QMT301 barriers surpass the minimum CSA and AASHTO design load requirements when considering 4-m barrier modules loaded on 2.4 m, whether or not there is a longitudinal connection and whether the loading is centered or eccentric.