TEST MATRICES FOR EVALUATING CABLE MEDIAN BARRIERS PLACED IN V-DITCHES

Cable barrier systems designed to be used in median ditches have been traditionally full-scale crash tested placed either within 4 ft from the slope break point (SBP) of a 4H:1V front slope or near the bottom of the ditch. Recently, there has been some discussion about proposing specific standard test conditions for cable barrier systems which are designed to be placed in a median ditch. The objective of this research was to propose a matrix of critical tests for cable barriers placed in median V-ditches. Critical tests were proposed based on the identification of those locations where the potential for override/underride is more likely, as indicated by an analysis of the simulated bumper trajectory of small cars, passenger sedans, and pickup trucks when trespassing a median V-ditch. The bumper trajectories as well as the vehicle kinematics were obtained using LS-DYNA computer simulations considering different ditch widths and slopes. Results from previous full-scale crash tests of cable systems placed in V-ditches were also considered in the assessment of the test matrices.