Testing and Evaluation of the Modified MELT (FHWA-RD-96-202)

The Modified Eccentric Loader Terminal (MELT) is one of the end terminals currently approved for use with W-beam guardrail systems. The MELT terminal has successfully met all evaluation criteria set forth in NCHRP Report 230. However, with the adoption of NCHRP Report 350 by FHWA as the official guidelines for crash testing of roadside safety features, it became necessary to retest the MELT terminal to the new guidelines. An effort was therefore undertaken by FHWA to evaluate the MELT terminal with the 2000P test vehicle according to NCHRP Report 350 guidelines.|Under a previous study, the MELT terminal was tested with the 2000P test vehicle in two tests, one a redirection test at the beginning of length-of-need and the other an end-on test. The MELT terminal failed to perform satisfactorily in both tests. As a result of these two failed crash tests, FHWA redesigned the MELT terminal. The redesigned terminal was then crash tested to evaluate its safety performance in accordance with NCHRP Report 350 guidelines. The Modified MELT terminal was judged to have performed satisfactorily in the end-on test, but failed in the redirection test.|Under this contract, FHWA made further modifications to the MELT in an effort to prevent rupture of the rail element which allowed the vehicle to penetrate the guardrail. These modifications included a redesigned shelf angle at post 2 and W-beam backup plates used at post 4, 5, 7, and 8. The new design was tested to evaluate its performance with the 2000P vehicle impacting the terminal at the beginning of length of need at a nominal speed of 100 km/in and at an angle of 20 degrees relative to the tangent section. This report presents the modifications, results, and evaluation of the crash test performed.|The modified MELT met all NCHRP Report 350 evaluation criteria for test designation 3-35.