Designing and Testing of Concrete Bridge Decks Reinforced with Glass FRP Bars Brahim Benmokrane 1 ; Ehab El-Salakawy 2 ; Amr El-Ragaby 3 ; and Thomas Lackey 4 Abstract: In addition to their high strength and light weight, fiber-reinforced polymer FRP composite reinforcing bars offer corrosion resistance, making them a promising alternative to traditional steel reinforcing bars in concrete bridge decks. FRP reinforcement has been used in several bridge decks recently constructed in North America. The Morristown Bridge, which is located in Vermont, United States, is a single span steel girder bridge with integral abutments spanning 43.90 m. The deck is a 230 mm thick concrete continuous slab over girders spaced at 2.36 m. The entire concrete deck slab was reinforced with glass FRP GFRP bars in two identical layers at the top and the bottom. The bridge is well instrumented at critical locations for internal temperature and strain data collection with fiber-optic sensors. The bridge was tested for service performance using standard truck loads. The construction procedure and field test results under actual service conditions revealed that GFRP rebar provides very good and promising performance. DOI: 10.1061/ASCE1084-0702200611:2217 CE Database subject headings: Bridge decks; Bridges, concrete; Fiber reinforced materials; Fiberglass; Field tests; Fiber optics. Introduction The expansive corrosion of steel reinforcing bars stands out as a significant factor limiting the life expectancy of reinforced concrete structures. In North America, significant temperature fluctuations and the use of deicing salts exacerbate the phenom- enon in parking garages and on bridge decks. Indeed, North America’s freeze–thaw cycles and heavy salt applications subject roads and bridges to quite severe environmental conditions. Furthermore, the expansive corrosion of steel causes cracking and spalling of concrete bridge decks, resulting in major rehabilitation costs and traffic disruption Yunovich and Thompson 2003. Problems related to expansive corrosion could be resolved by protecting the steel reinforcing bars from corrosion-causing agents or by producing rebars made of noncorrosive materials. Fiber-reinforced polymer FRP composite reinforcement is one such alternative, which has been used successfully in many industrial applications and more recently has been used as concrete reinforcement in bridge decks and other structural elements Rizkalla and Tadros 1994; Saadatmanesh and Ehsani 1996; Japan Concrete Institute 1997; Benmokrane and Rahman 1998; Rizkalla et al. 1998; Hassan et al. 1999; Humar and Razaqpur 2000; Khanna et al. 2000; Tadros 2000; Benmokrane et al. 2001a; Steffen et al. 2001; Yost and Schmeckpeper 2001; Benmokrane and El-Salakawy 2002; Bradberry and Wallace 2003. Using noncorrosive FRP reinforcing bars in concrete bridge decks can extend service life, reduce maintenance costs, and improve life-cycle cost efficiency. Moreover, FRP rebars may also reduce construction costs by eliminating the need for mem- brane and pavement items. Typical concrete bridge deck slabs in Canada and the United States consist of two mats of steel bars e.g., traditional black steel, galvanized steel, and epoxy-coated steel bars with an increased concrete cover up to 75 mm at the top, a membrane, and pavement as added corrosion protection. It should be noted that the concrete structural deck slab is the bridge component most vulnerable to corrosion deterioration because it is directly exposed to high concentrations of chlorides used for snow and ice removal. Since glass fiber-reinforced polymer GFRP rebar is more economical than the available types carbon and aramid of FRP rebars, it is more attractive for infrastructure applications and to the construction industry. In fact, several concrete bridge decks have recently been built in North America with GFRP composite rebars GangaRao et al. 1997; Bradberry 2001; Stone et al. 2001; Nanni and Faza 2002; El-Salakawy and Benmokrane 2003; El-Salakawy et al. 2003b; Huckelbridge and Eitel 2003. The new Canadian Highway Bridge Design Code CAN/CSA-S6-00 CSA Int. 2000 includes Section 16 on using FRP composite bars as nonprestressed and prestressed reinforcement for concrete bridges slabs, girders, and barrier walls. Furthermore, several codes and design guidelines for concrete structures reinforced with FRP bars have been published recently ISIS 2001; CSA Int. 2002; ACI 2003. Through the NSERC Industrial Research Chair in Fiber- Reinforced Polymer Composite Reinforcement for Concrete Infrastructures, a joint effort with the Ministry of Transportation of Quebec MTQ was established to develop and implement FRP reinforcement for concrete bridges. This effort initially 1 NSERC Research Chair Professor in FRP Reinforcement for Concrete Structures, Dept. of Civil Engineering, Univ. of Sherbrooke, Sherbrooke PQ, Canada J1K 2R1 corresponding author. E-mail: brahim.benmokrane@usherbrooke.ca 2 Research Associate Professor, Dept. of Civil Engineering, Univ. of Sherbrooke, Sherbrooke PQ, Canada. E-mail: ehab.elsalakawy@ usherbrooke.ca 3 PhD Candidate, Dept. of Civil Engineering, Univ. of Sherbrooke, Sherbrooke PQ, Canada J1K 2R1. 4 Bridge Engineer, Vermont Agency of Transportation, Montpelier, VT. Note. Discussion open until August 1, 2006. Separate discussions must be submitted for individual papers. To extend the closing date by one month, a written request must be filed with the ASCE Managing Editor. The manuscript for this paper was submitted for review and pos- sible publication on January 9, 2004; approved on December 7, 2004. This paper is part of the Journal of Bridge Engineering, Vol. 11, No. 2, March 1, 2006. ©ASCE, ISSN 1084-0702/2006/2-217–229/$25.00. JOURNAL OF BRIDGE ENGINEERING © ASCE / MARCH/APRIL 2006 / 217