弯钩型钢纤维混凝土弯曲韧性试验研究

Experimental Study on Bending Toughness of Hooked Steel Fiber Concrete

摘要:

通过对5种类型钢纤维混凝土基本力学性能试验，对比研究钢纤维类型、钢纤维掺量对混凝土抗压强度、弹性模量、劈拉强度的影响，确定弯钩型钢纤维选型。基于三分梁、切口梁试验和配合比优化研究其钢纤维掺量、长径比对混凝土弯曲韧性的影响。结果表明：弯钩型钢纤维对抗压强度、弹性模量、劈拉强度增强作用较好。随着长径比和钢纤维掺量增加，弯曲韧性指数、残余强度明显提高。钢纤维掺量为30～35 kg/m³，各阶段残余弯拉强度都随之提高，且优化配合比可使残余阶段强度提高约12.9%。

Abstract:

Through the basic mechanical property tests on five types of steel fiber concrete, the influence of steel fiber type and steel fiber dosage on the compressive strength, elastic modulus and splitting tensile strength of concrete is studied and compared. The selection of hooked steel fiber is determined. Based on the test of three-divided beam and coped beam, and the mix ratio optimization, the influence of steel fiber content and length-diameter ratio on the bending toughness of concrete is studied. The results show that the hooked steel fiber has a better effect on enhancing the compressive strength, elastic modulus and splitting tensile strength of concrete. With the increase of length-diameter ratio and steel fiber dosage, the bending toughness index and residual strength increase significantly. When the steel fiber dosage is 30~35 kg/m³, the residual bending-tensile strength of each stage increases as the steel fiber dosage increases, and the residual strength can be increased by 12.9% by optimizing the mix ratio.