Development and Testing of a Concrete Median Barrier for Flood-Prone Areas

Abstract

Concrete median barriers are designed to mitigate serious cross-median crashes by preventing penetration of errant vehicles into oncoming traffic. When implemented in flood-prone areas, however, solid concrete median barriers can act as a dam to floodwaters, as recently seen in the U.S. in Texas during Hurricane Harvey, or in Louisiana and Pennsylvania following severe storms. This raises the height of the floodwaters and increases the severity of flooding on highways and surrounding roads and communities. To reduce flooding, new median barrier options with openings were investigated. Finite element simulations were used to aid investigation and evaluation of the designs, and laboratory testing was performed to evaluate the hydraulic efficiency of barrier designs in a variety of simulated flood conditions. A concrete single-slope profile median barrier with a large scupper was selected for crash testing following Manual for Assessing Safety Hardware (MASH) Test Level 4 (TL-4) impact conditions and evaluation criteria. The median barrier design was deemed MASH compliant and is ready for implementation in areas susceptible to flooding, with the goal of reducing flooding severity, decreasing associated risk to motorists, and reducing the level of flood damage to both highways and surrounding areas.