BFRP筋局部钢纤维混凝土梁斜截面抗剪性能试验研究

Experimental Study on Shear Behavior of Concrete Beams Reinforced with Local Steel Fiber and BFRP Bars

为了研究BFRP筋钢纤维混凝土梁斜截面的抗剪性能,以BFRP筋钢纤维混凝土梁为研究对象,开展了9根BFRP筋钢纤维混凝土梁的斜截面抗剪承载力试验,分析了试验构件的破坏形态,探讨了剪跨比、BFRP筋配筋率、钢纤维体积掺量、钢纤维范围等参数对BFRP筋钢纤维混凝土梁抗剪性能的影响。结果表明,BFRP筋钢纤维混凝土梁的破坏形态以剪切破坏为主;试验梁的斜截面抗剪承载力随着剪跨比的增大而下降,随着纤维掺量和BFRP筋配筋率的增大而提高;支座以内剪跨范围设置钢纤维能够较好地改善BFRP筋混凝土梁的斜截面抗剪性能。最后,由试验数据拟合得到BFRP筋钢纤维混凝土梁斜截面抗剪承载力计算公式,公式计算值与试验结果吻合较好。研究丰富了FRP筋混凝土复合结构斜截面设计理论,对FRP筋钢纤维混凝土复合结构在实际工程的应用具有参考价值。

In order to study the shear resistance of the inclined section of steel fiber reinforced concrete beams with BFRP bars,this paper takes the steel fiber reinforced concrete beams with BFRP bars as the research object,and carries out the shear capacity tests of 9 steel fiber reinforced concrete beams with BFRP bars.The effects of failure mode,shear span ratio,BFRP reinforcement ratio,steel fiber volume fraction,and steel fiber range on the shear resistance of steel fiber reinforced concrete beams with BFRP bars are analyzed.The results show that the failure mode of steel fiber reinforced concrete beams reinforced with BFRP is mainly shear failure;The shear capacity of the inclined section decreases with the increase of shear span ratio,and increases with the increase of fiber content and BFRP reinforcement ratio;Setting steel fiber within the shear span of the support can better improve the shear resistance of the inclined section of the concrete beam with BFRP reinforcement.Finally,the formula for calculating the shear capacity of steel fiber reinforced concrete beams with BFRP bars is obtained by fitting test data,and the calculated results of the formula are consistent with the experimental results.The research enriches the design theory of inclined section of FRP reinforced concrete composite structure,and has reference value for the application of FRP reinforced steel fiber concrete composite structure in practical projects.