The Truck Thrie Beam Transition (Triple T), an 813-mm (32-in.) thrie beam transition, was developed under a recently completed pooled funds study. The study involved 23 states, the District of Columbia, and the Federal Highway Administration. The Triple T was crash-tested according to Performance Level 2 (PL2) requirements of the 1989 AASHTO guide. The transition performed acceptably after modifications were made to the end terminal connection. For testing, the 813-mm (32-in.) transition was attached to the end of the vertical-faced concrete parapet bridge railing. The Triple T is acceptable for use on other PL2 bridge railings if suitable attachment to the bridge railing (such as the modified end terminal connector) is used.


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Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: p. 70-79
  • Monograph Title: Geometric design, roadside safety features, roadside hardware monitoring, and scenic loop tours
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00714993
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Dec 26 1995 12:00AM