Ductility of concrete beams reinforced with hyprid frp rebars

Abstract EN

Aiming to improve the ductility of FRP reinforced concrete members, the flexural behavior of concrete beams reinforced with innovative hybrid FRP rebars was investigated.

Four simply supported beams (127 x 200 x 1730 mm) were cast using normal and high strength concrete mixes and different reinforcement ratios.

Similar beams were reinforced using GFRP bars and steel.

The in-house manufactured FRP bars were 9.5 mm in diameter with a sand-coated surface.

The hybrid rebars were manufactured by replacing 10 percent of the glass fiber volume with 0.35 mm-diameter nylon threads.

The nylon thread is more ductile than the glass fibers with improved mechanical properties.

The beams were tested in flexure under four-point loading till failure.

The structural behavior was compared in terms of ultimate loads, deformations and modes of failure.

The results demonstrated the efficiency of the hybridization in improving the ductility of test beams.

Design equations based on the strain compatibility and equilibrium of forces were derived to predict the load capacity of the beams reinforced with the hybrid rebars and were found to be adequate based on the available experimental results.