Two Test Level 4 Bridge Railing and Transition

Two Test Level 4 Bridge Railing and Transition Systems For Transverse Timber Deck Bridges by Ronald K. Faller, Ph. D. , P. E. Michael A. Ritter, P. E. Barry T. Rosson, Ph. D. , P. E. Michael D. Fowler Sheila R. Duwadi, P. E.

Introduction • Bridge railing research • Bridge deck systems - concrete - timber (longitudinal vs. transverse) • Need for high performance crashworthy • railings FPL, FHWA, & Mw. RSF

Research Objectives • Two bridge railings for transverse timber deck • • • bridges - steel - wood High performance railing systems (TL-4) Two approach guardrail transitions Force level determination

Bridge Railing History • Bridge railing design - 10 -kip static load method - LRFD method - computer simulation modeling • Full-scale crash testing - NCHRP Report 230 - AASHTO Guide Specifications - NCHRP Report 350

Test Requirements and Evaluation Criteria • NCHRP Report 350 • Three required tests - 820 C - 100 kph & 20 deg - 2000 P - 100 kph & 25 deg - 8000 S - 80 kph & 15 deg • Structural adequacy, occupant risk, & vehicle trajectory after collision

Wood Bridge Rail Steel Bridge Rail

Conclusions • Two bridge railings for transverse timber deck bridges • Wood and steel rail options • Two approach guardrail transitions • Crash tests met the TL-4 evaluation criteria • Modifications based on load data