FRP筋混凝土短梁抗剪性能试验研究及承载力计算

Experimental study and calculation of shear capacity of FRP-reinforced concrete short beams

为分析梁高、剪跨比、腹筋率等参数对纤维增强聚合物(FRP)筋混凝土短梁抗剪承载力的定量影响,并验证前期基于拉杆拱模型提出的抗剪承载力计算方法的科学合理性,对11根玄武岩FRP筋混凝土短梁开展了剪切破坏试验,试验梁最大梁高为1.2 m.试验结果表明,梁高、剪跨比、水平腹筋率、竖向腹筋率均对FRP筋混凝土短梁的抗剪承载力有显著影响.当梁高由300 mm增大到1200 mm,试验梁的无量纲极限抗剪强度下降46.7%.当水平腹筋率由0增大至1.0%,试验梁的无量纲极限抗剪强度提高40.5%.基于拉杆拱模型提出的抗剪承载力计算式可以合理反映梁高、剪跨比、水平腹筋率等因素的影响规律,计算结果与本试验结果及搜集试验数据均吻合良好.

To analyze the quantitative effect of parameters such as beam height,shear-span ratio,and web reinforcement ratio on the shear capacity of fiber reinforced polymer(FRP)reinforced concrete short beams,and to verify the rationality of the calculation method of shear capacity proposed on the basis of tie-arch model in the early stage,shear failure tests were conducted on 11 basalt FRP reinforced concrete short beams,with a maximum beam height of 1.2 m.The experimental results indicate that beam height,shear-span ratio,horizontal and vertical web reinforcement ratio have a significant effect on the shear capacity of FRP reinforced concrete short beams.When the beam height increases from 300 mm to 1200 mm,the non-dimensional ultimate shear strength of the test beam decreases by 46.7%.When the horizontal reinforcement ratio increases from 0 to 1.0%,the non-dimensional ultimate shear strength of the test beam increases by 40.5%.The shear capacity calculation formula proposed by tie-arch model can reasonably reflect the influence laws of factors such as beam height,shear-span ratio,and horizontal web reinforcement ratio.The calculation results are better consistent with the results of this experiment and collected experimental data.