The application of deicing salt on roads during the winter is one of the main reasons for steel corrosion in reinforced-concrete pavements in cold-weather regions such as Canada and the Northern United States. Steel corrosion creates internal stresses in the concrete that cause the concrete to burst. This reduces the service life of pavements and increases maintenance costs. This study presents a long-term field test of a continuously reinforced-concrete pavement (CRCP) reinforced with glass fiber-reinforced polymer (GFRP) bars located on Highway 40 West (Montreal, Quebec). The design procedures, construction details, performance, and monitoring results for a 306-m-long section of GFRP-CRCP are presented. Three different types of fiber-optic sensors were used to monitor the pavement behavior and to evaluate the long-term performance of this type of CRCP. The field inspection ran for 6 years after the time of construction, and the data covering 30 months were analyzed. The concrete crack width, concrete crack spacing and rate, concrete temperature, concrete strain, and GFRP-bar strain behavior were recorded and investigated. The GFRP-CRCP and a 94-m-long stretch of steel-CRCP on that highway were compared in terms of crack width, spacing, and rate. Site inspection showed that neither type of pavement exceeded the crack-width limit of 1.0 mm set by the available design standard for pavement structures. The crack rate of the CRCP reinforced with GFRP bars was generally lower than that with steel bars. Moreover, the field test results after 6 years under actual service conditions revealed that GFRP-CRCP provides very competitive performance in comparison to steel-CRCP. Lastly, design equations were developed and proposed to determine the longitudinal-reinforcement ratio for the GFRP-CRCP based on the available design standard.

This paper presents the difference in behavior between hollow-core fiber reinforced polymer-concrete-steel (HC-FCS) columns and conventional reinforced concrete (RC) columns under vehicle collision in terms of dynamic and static forces. The HC-FCS column consisted of an outer FRP tube, an inner steel tube, and a concrete shell sandwiched between the two tubes. The steel tube was hollow inside and embedded into the concrete footing with a length of 1.5 times the tube diameter while the FRP tube stopped at the top of footing. The RC column had a solid cross-section. The study was conducted through extensive finite element impact analyses using LS-DYNA software. Nine parameters were studied including the concrete material model, unconfined concrete compressive strength, material strain rate, column height-to-diameter ratio, column diameter, column top boundary condition, axial load level, vehicle velocity, and vehicle mass. Generally, the HC-FCS columns had lower dynamic forces and higher static forces than the RC columns when changing the values of the different parameters. During vehicle collision with either the RC or the HC-FCS columns, the imposed dynamic forces and their equivalent static forces were affected mainly by the vehicle velocity and vehicle mass.

This paper presents the behavior of hollow-core fiber-reinforced polymer–concrete–steel (HC-FCS) columns under cyclic torsional loading combined with constant axial load. The HC-FCS consists of an outer fiber-reinforced polymer (FRP) tube and an inner steel tube, with a concrete shell sandwiched between the two tubes. The FRP tube was stopped at the surface of the footing, and provided confinement to the concrete shell from the outer direction. The steel tube was embedded into the footing to a length of 1.8 times the diameter of the steel tube. The longitudinal and transversal reinforcements of the column were provided by the steel tube only. A large-scale HC-FCS column with a diameter of 24 in. (610 mm) and applied load height of 96 in. (2438 mm) with an aspect ratio of four was investigated during this study. The study revealed that the torsional behavior of the HC-FCS column mainly depended on the stiffness of the steel tube and the interactions among the column components (concrete shell, steel tube, and FRP tube). A brief comparison of torsional behavior was made between the conventional reinforced concrete columns and the HC-FCS column. The comparison illustrated that both column types showed high initial stiffness under torsional loading. However, the HC-FCS column maintained the torsion strength until a high twist angle, while the conventional reinforced concrete column did not.