Design and Testing of MASH TL-3 Anchored Precast Narrow Base Roadside Concrete Barrier

This paper presents the design and development of an anchored precast portable concrete barrier (PCB) with narrow base for the Maryland Department of Transportation State Highway Administration (MDOT SHA) in the U.S. The PCB was designed for roadside applications with an F-shape profile on the impact side and a single-slope profile on the non-impact side. It was evaluated for its crashworthiness according to the safety-performance evaluation guidelines included in the American Association of State Highway and Transportation Officials (AASHTO) Manual for Assessing Safety Hardware (MASH). The researchers first evaluated an existing barrier design detail of the PCB using finite element (FE) simulations. The results of the simulations showed that the existing barrier design was inadequate for satisfying MASH Test Level 3 (TL-3) crashworthiness performance criteria. The design was then modified by strengthening the concrete reinforcement, connections, and anchorage, while preserving the overall dimensions and its unique narrow base feature. The modified design was initially evaluated through FE simulations. Simulation results showed that it contained and redirected the striking vehicles acceptably and was likely to meet the MASH TL-3 evaluation criteria in full-scale crash testing. Subsequently, the modified PCB design was subjected to full-scale crash testing with MASH Test 3-11 and Test 3-10 conditions. The modified design of the anchored Maryland PCB with narrow base met the performance criteria for MASH TL-3 for longitudinal barriers.