EXPERIMENT STUDY ON THE FLEXURAL BEHAVIOUR OF HYBRID BFRP/STEEL REINFORCED CONCRETE BEAMS

Abstract

Abstract: A total of ten concrete beams, including one reinforced with BFRP, one reinforced with steel, and eight reinforced with hybrid BFRP and steel, were designed and prepared. Experiment tests were carried out to investigate the effect of reinforcement area ratio on the flexural behaviour of hybrid BFRP/steel reinforced concrete beams with a low and high reinforcement ratio. The flexural capacity, failure mode, flexibility deformation, crack distribution and ductility performance of the hybrid BFRP/steel reinforced concrete beams were analyzed and compared with the BFRP reinforced beam as well as the steel reinforced beam. The results indicated that there are two main failure modes: the hybrid BFRP/steel reinforced concrete beams with high reinforcement ratio fails by crushing of concrete in compression and either yielding of steel and the test beams with low reinforcement ratio fails by crushing of concrete in compression and either rupture of FRP in tension. The load-deflection curves of the hybrid reinforced concrete beams show three linear characteristics including the turning points corresponding to the cracking load and the yield of the steel bars. The ultimate bearing capacity of the hybrid reinforced concrete beams, which is found to be increased with the increase of area ratio, is slightly lower than that of BFRP reinforced concrete beams, but it is higher than that of reinforced concrete beams. The ductility of hybrid reinforced concrete beams are all larger than that of steel reinforced concrete beams. The lower the reinforcement ratio, the greater the reinforcement area ratio and the higher the ductility coefficient. To meet the requirements of structural seismic design specifications, it is recommended that the reinforcement area ratio is controlled to be not less than 0.6.

Key words: BFRP bar, hybrid reinforcement concrete beams, flexural capacity, reinforcement area ratio, ductility

CLC Number:

TB332

KONG Xiang-qing, YU Yang, XING Li-li, HAN fei. EXPERIMENT STUDY ON THE FLEXURAL BEHAVIOUR OF HYBRID BFRP/STEEL REINFORCED CONCRETE BEAMS[J]. Fiber Reinforced Plastics/Composites, 2018, 0(8): 48-54.

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