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对单调和循环荷载下普通以及纤维混凝土梁的抗弯性能进行分析。在12根梁的顶部和底部配置纵向螺纹钢和横向箍筋,并在强度30MPa混凝土中掺入体积分数为1%的钩状钢纤维。对梁进行三点弯曲试验,梁截面为正方形,边长为150mm,长度600mm,保护层厚度分别为5,15,25mm。研究结果表明:随着纤维含量的增加,梁的承载力增加,延性更好。同时减少了循环荷载下的退化。此外,加入纤维降低了保护层开裂的程度,在保护层厚度较大时也是如此。将普通混凝土抗剪强度的解析表达式拓展到钩状钢纤维混凝土试验梁,根据荷载-挠度曲线,采用非线性有限元程序(DRAIN-2DX)进行抗剪强度计算。在考虑规范中纤维混凝土抗压和抗拉性能的基础上,对程序进行修正,检验试验数据。最后,为解决单筋截面的延性问题,对纵横向钢筋的比率进行了优化。此外,得到了抗剪强度并与欧洲和国际标准进行了比较。
The bending performance of ordinary and fiber reinforced concrete beams under monotonic and cyclic loadings was analyzed. Longitudinal rebar and transverse stirrups were arranged at the top and bottom of the 12 beams, and hooked steel fibers with a volume fraction of 1% were mixed in a concrete with a strength of 30 MPa. Beam three-point bending test, the beam cross-section is square, the side length of 150mm, length 600mm, protective layer thickness of 5,15,25 mm. The results show that as the fiber content increases, the bearing capacity of the beam increases and the ductility is better. While reducing the degradation under cyclic loading. In addition, the addition of fibers reduces the degree of cracking of the protective layer, as is the case with thicker protective layers. The analytic expression of ordinary concrete shear strength was extended to the hooked steel fiber reinforced concrete test beam, and the shear strength was calculated by nonlinear finite element program (DRAIN-2DX) according to the load-deflection curve. On the basis of considering the compressive and tensile properties of the fiber concrete in the specification, the program is revised and the test data is verified. Finally, in order to solve the ductility problem of single section, the ratio of vertical section and horizontal section is optimized. In addition, shear strength is obtained and compared with European and international standards.