关键词: 破坏形态, 极限荷载, 跨中挠度, 撕裂破坏, 剥离破坏, BFRP, 钢筋混凝土梁

Abstract: In order to study the impact of different layers of basalt fiber reinforced polymer(BFRP)on the bending performance of reinforced concrete beams, three dividing point loading experiments were performed on the beams with a separate hydraulic jack. The failure modes, crack loads, yield loads, ultimate loads and the mid-span deflections corresponds to the above loads of the beams reinforced with 1, 2 and 3 layers of BFRP at the bottom of the beam were observed respectively and compared with the reference beam. The experiment results showed that, with the increasing number of the pasted BFRP layers, failure modes of the beams were changed, the number of primary cracks were decreased, crack loads, yield loads and ultimate loads were increased with varying degrees. The ultimate loads were respectively increased by 7.92%(1 layer), 23.66%(2 layers)and 29.31%(3 layers), and corresponding span deflections were also respectively decreased by 14.54%, 26.65% and 28.81%. When 1~2 layers of the BFRP were pasted, ductility factors of the beams were increased and the ductility factor was reduced when 3 layers of BFRP were pasted. The generation and expansion of the bending cracks were the main cause of the failure of BFRP. The flexural behavior of the beams was not proportional to the increase of the number of the BFRP layers. Taking together beams strengthened by 2 layers of BFRP, not only the bending bearing capacity and ductility have been greatly improved, but also the deflection has been greatly reduced which has good economic performance.

Key words: ultimate load, span deflection, tearing damage, debonding damage, failure modes, BFRP, reinforced concrete beams