Crash Testing and Evaluation of F-Shape Barriers on Slopes

The TxDOT Roadway Design Manual currently suggests that concrete barrier not be placed on slopes steeper than 10H:1V. This suggestion has limited the placement of concrete barriers to narrow, flat, paved medians or at the edge of the shoulder. Based on the results of full-scale crash testing, researchers determined that TxDOT's cast-in-place permanent F- shape barrier and the precast free-standing X-bolt F-shape barrier are suitable for placement on roadside and median foreslopes of 6H:1V or less. Additionally, these barriers are suitable to be placed at any lateral offset from the roadway edge, and for any width of depressed V-ditch median as long as the barrier is placed at its center. Further, similar or better performance would be expected for barrier placement on more gentle (e.g., 8H:1V) slopes. Increasing the maximum slope on which median barriers can be placed will allow many installations to be placed further from the travelway, which in turn will most likely lead to a reduction in barrier impact frequency and severity.