Performance assessment of UHPC composite barriers under velocity impacts

This study investigates the structural performance of a novel UHPC-based composite barrier designed to enhance roadside safety under vehicular impacts. The barrier adopts a three-layer configuration of Ultra High Performance Concrete (UHPC), High Strength Concrete (HSC), and Normal Concrete (NC), aiming to balance energy absorption, structural integrity, and construction feasibility. A finite element model is developed in ABAQUS to simulate vehicle-barrier collisions, incorporating the experimentally derived bond parameters and cohesive elements. Under a 25-ton truck impact at 96.5 km/h, the simulation indicates that only the directly impacted 4-meter barrier segment undergoes significant damage. Furthermore, the outer UHPC layer bears the majority of the stress and dissipates most of the impact energy, while internal HSC and NC layers remain structurally stable. The stress levels in the reinforcement components remain within the elastic domain, as evidenced by values of 189 MPa in the steel bars and 268 MPa in the shear connectors, thereby confirming structural integrity. The investigation provides a promising foundation for future experimental validation and the development of practical UHPC barrier designs for highway applications. • A novel UHPC-based composite barrier was developed, comprising an outer UHPC shell, HSC transition layer, and NC core. • A validated simulation model incorporating the KCC model and cohesive zone elements was implemented in ABAQUS, using shear bond strength obtained from experiments. • Compared to RC conventional barriers, the proposed system demonstrates the following advantages: – The UHPC layer serves as the primary energy absorber, confining severe damage to a single 4-meter barrier segment; – The layered configuration ensures a balanced integration of structural performance, controlled damage localization, and ease of modular replacement.