进行了10根纤维–钢筋自密实混凝土简支梁在两点对称集中荷载作用下的抗剪性能试验.主要参数包括不同纤维类型和掺量、不同箍筋布置.研究了钢纤维和混杂纤维对极限剪力、剪力–位移曲线、破坏模式等影响,分析了钢纤维、混杂钢纤维和合成纤维及纤维与箍筋共同作用时替代按构造布置箍筋的可行性.研究表明:掺入钢纤维或混杂纤维可显著提高梁的极限剪力;掺加50 kg/m3的钢纤维在改善梁的极限剪力方面好于混杂钢纤维30 kg/m3和合成纤维5 kg/m3的混杂纤维.掺加50 kg/m3的钢纤维可以替代按构造布置的φ6.5@150的箍筋.混杂钢纤维30 kg/m3及合成纤维5 kg/m3和φ6.5@250的箍筋共同作用可以替代按构造布置的φ6.5@150或φ8@150的箍筋.钢纤维50 kg/m3和φ6.5@250的箍筋共同作用使梁从脆性的剪切破坏转变为延性的弯曲破坏.%An experimental investigation on the shear performance of fiber reinforced self-consolidating concrete beams was carried out. Ten simply supported beams were tested under symmetrically placed two-point concentrated loading. The main parameters are various fiber types, different fiber contents and different stirrups. The influence of steel fibers, hybrid steel fibers and synthetic fibers on the ultimate shear force, shear force-displacement curve and failure mode were studied. The possibility of using different fibers or the composite effect of fibers and stirrups to replace the shear stirrups were analyzed. The experimental results show that the ultimate shear force was obviously increased by steel fibers and hybrid fibers. The ultimate shear force of beam with 50 kg/m3 steel fibers is better than that of hybrid steel fibers 30 kg/m3 and synthetic fibers 5 kg/m3 . The stirrups ofφ6.5@150 placed according to constructive reinforced stirrups can be replaced by 50 kg/m3 steel fibers. The stirrups of φ6.5@150 or φ8@150 placed according to constructive reinforced stirrups can be replaced by composite effect of hybrid steel fibers 30 kg/m3 , synthetic fibers 5 kg/m3 and stirrups of φ6.5@250. The composite effect of 50 kg/m3 hybrid fibers and stirrups of φ6.5@250 can change the failure mode from a brittle shear collapse into a ductile flexural mechanism.
展开▼
