STRUCTURAL BEHAVIOR EVALUATION OF HIGH-STRENGTH CONCRETE BEAMS REINFORCED WITH PRESTRESSED PRISMS USING FIBER OPTIC SENSORS

Thirteen high-strength concrete, simply supported composite beams with a span of 9 ft (2743 mm) were tested to failure, and their general st ructural bending properties were evaluated and reported Precast prestr essed concrete prisms were used as main tension reinforcement in all t he test specimens. High-strength concrete with compressive strength f( c)' in the range of 12,000 to 14,000 psi (84.4 to 98.5 MPa) was used f or both prisms and situcast main beams. Test results showed that the p resence of precast prestressed prisms as tension reinforcement signifi cantly increases the cracking capacity and improves flexural stiffness of the test beams, with consequent reduction in deflection and crack width at service load. A novel fiber optic sensor, Bragg grating, was used to develop smart structures by instrumenting all the test beams f or direct and quantitative measurement of load-induced strains in the concrete and reinforcement. Typical results, such as average steel str ains and crack widths obtained from fiber optic Bragg grating sensors, are evaluated.