摘要: |
A tie-down system was developed for use with Iowa's steel H-section temporary barrier. For this system, the original barrier connection detail was modified in order to simplify barrier attachment to one another as well as to more easily accommodate deviations in horizontal and vertical alignment. At each barrier joint, two steel shear plates were positioned within an opening on the adjacent barrier section and held in place with two steel drop pins. Four steel angle brackets were welded to the barrier's base at every joint in order to allow for the barriers to be rigidly attached to the concrete bridge deck using drop-in anchors. Two full-scale vehicle crash tests, using -ton pickup trucks, were performed on the steel H-section barrier system. Due to vehicle snag and subsequent vehicle rollover, the first test was unsuccessful. Following minor design modifications, the barrier system was retested. The second test was successfully conducted on the tied-down steel H-barrier system which safely redirected the pickup truck. The tests were conducted and reported in accordance with the requirements specified in the National Cooperative Highway Research Program (NCHRP) Report No. 350, Recommended Procedures for the Safety Performance Evaluation of Highway Features. The safety performance of the tie-down system for use with Iowa's steel H-section temporary barrier was determined to be acceptable according to the Test Level 3 (TL-3) evaluation criteria specified in NCHRP Report No. 350. |