钢纤维高强混凝土箍筋梁抗剪性能试验

Experimental study on shear resistance of steel fiber reinforced high strength concrete beams

为了提高高强混凝土的韧性和抗剪能力，在高强钢筋混凝土梁中掺入钢纤维．对20根（ffcu=52．4-84．7）钢纤维高强混凝土箍筋梁（ρf=0．5％-1．5％）和2根高强混凝土箍筋梁对比试件进行了试验．试验的主要变化参数为钢纤维体积掺率、钢纤维种类、配箍率和混凝土强度．试验结果表明钢纤维能够显著地改善梁的抗剪性能．基于试验结果，分析了钢纤维、箍筋、混凝土的强度和剪跨比对梁的斜截面抗裂和抗剪承载力的影响．在考虑钢纤维影响的基础上，提出了与普通钢筋混凝土梁斜截面计算公式相协调的钢纤维混凝土梁的斜截面开裂和极限承载力计算的经验公式．

In order to improve the toughness and shear resistance of high strength concrete, steel fibers were added into the reinforced high strength concrete beams. 20 steel fiber reinforced high strength concrete （ffcu = 52.4 - 84.7 MPa） beams with stirrups and 2 contrastive beams without steel fiber were tested. The main vari- ables were steel fiber volume fraction, steel fiber type, stirrup content, concrete strength and shear span -effective depth ratio. The test results showed that the diagonal cracking strength and shear strength of the beams were improved significantly by steel fiber. Based on the test results, some empirical formulas to predict the diagonal cracking strength and shear strength of steel fiber reinforced high strength concrete beams were suggested, which were coordinated with those for reinforced concrete beams.