Bridge Deck and Guardrail Anchorage Detailing for Sustainable Construction

Abstract

This paper investigates the use of glass fiber reinforced polymer (GFRP) bar bents as stirrups at the joint between the steel posts of a bridge guardrail system with a deck slab cantilever. In addition, GFRP bars with headed ends are used for better anchorage at the postdeck slab joint. Four full-scale cantilever post specimens were erected and tested to collapse. Two specimens were reinforced with steel bars as control specimens, whereas the other two specimens were reinforced with GFRP straight bars, bent bars, and headed bars at applicable locations. Similar failure modes were observed in all specimens because of curb external side face breakout. Failure occurred in unconfined concrete cover because of significant compressive and frictional shear stresses and also torsional effects, resulting in concrete spalling at the side face of the cantilever at the bottom of the posts. Although it is recommended to consider larger edge distance of the post to prevent premature failure in the unconfined concrete cover, the obtained experimental capacity of the postcurb region was concluded to be sufficient to resist design loads. To calculate the share of the design lateral loads received by each post, a linear finite-element analysis (FEA) and a simplified FEA were used. The analysis showed that the share of each post decreases with decrease in spacing between posts.