Various government agencies install timber guardrails on scenic highways and roads in lieu of conventional steel guardrails for aesthetic reasons. Most acceptable timber guardrails rely on a continuous steel backing member to carry the large tensile forces caused by vehicle impact and transfer load to the posts. However, these guardrails are relatively expensive and heavy due to their use of large, solid-sawn timber sections. This study focuses on the development and structural testing of a novel timber guardrail that consists of a hardwood glued-laminated member strengthened with a fiber-reinforced polymer (FRP). The FRP acts in place of steel to carry the impact-induced tension and the guardrail is significantly shallower and lighter than conventional timber guardrails. This paper details the analysis of the guardrail response under vehicle impact, the development and testing of a unique and easily installed rail-to-rail field splice connection capable of carrying the tensile forces caused by vehicle impact, and the evaluation of guardrail durability in exterior conditions. In addition, the structural performance of the guardrail was assessed using experiments that produced the simultaneous tension and flexure forces expected during vehicle impact using a single hydraulic actuator and a three-point bending test apparatus. Based on the development and testing documented in this paper, the FRP-reinforced timber guardrail is expected to be capable of passing required vehicle crash tests.
|Number of pages||11|
|Journal||Construction and Building Materials|
|State||Published - Nov 2006|
Bibliographical noteFunding Information:
This project was funded by the New England Transportation Consortium under Grant No. NETC 00-3. The authors also gratefully acknowledge the assistance of undergraduate student researchers Stephen Cotton and Chad Gibson, who were supported by the US National Science Foundation Grant No. EEC-0097500. The views expressed in this manuscript are solely those of the authors and this paper does not constitute a design guide or specification.
- Bolted timber connection
- Reinforced timber
- Vehicle impact
ASJC Scopus subject areas
- Civil and Structural Engineering
- Building and Construction
- Materials Science (all)