（1 天津城建大学天津市土木建筑结构防护与加固重点实验室， 天津 300384； 2 天津大学建筑工程学院， 天津 300072）

［摘要］通过对Z形试件进行直剪试验，研究钢纤维超高强混凝土的抗剪性能，着重分析了钢纤维类型、体积率和钢筋配箍率对钢纤维超高强混凝土抗剪强度的影响。试验结果表明：与螺旋钢纤维相比，超细钢纤维能够更好地提高试件的抗剪强度；在合理的体积率范围内（超细纤维的最优抗剪强度体积率位于0-5%～1-5%之间，而螺旋钢纤维的最优抗剪强度体积率位于1-5%～2-5%之间），钢纤维超高强混凝土的抗剪强度随着钢纤维体积率增大而显著增大；另外，钢纤维超高强混凝土的延性和抗剪强度随钢筋配箍率的增大而显著提高。

［关键词］钢纤维超高强混凝土； 直剪试验； 抗剪强度； 延性

中图分类号：TU528文献标识码：A文章编号：1002-848X(2016)15-0042-05

Direct shear experimental research on shear properties of steel fiber reinforced ultra high strength concrete

Zhao Yongjiao1, Liu Zhongxian1, Xu Shenchun2, Wu Pengtao1

(1 Tianjin Key Laboratory of Civil Structure Protection and Reinforcement, Tianjin ChengJian University, Tianjin 300384, China; 2 School of Civil Engineering, Tianjin University, Tianjin 300072, China)

Abstract:Shear properties of steel fiber reinforced ultra high strength concrete were investigated by direct shear tests on Z-shaped specimens, and the study emphasized on the influences of steel fiber type, volume ratio and stirrup reinforcement ratio on the shear strength of steel fiber reinforced ultra high strength concrete. The test results show that: compared with spiral steel fiber, micro steel fiber can obviously improve shear strength of specimens. Within a reasonable range of the volume ratio (regarding the shear strength, optimum volume ratio ranges 0-5% to 1-5% for micro steel fiber, and 1-5% to 2-5% for spiral steel fiber), the shear strength of steel fiber reinforced ultra high strength concrete increases significantly with the increase of steel fiber volume ratio. Additionally, the ductility and shear strength of steel fiber reinforced ultra high strength concrete also increases significantly with the increase of stirrup ratio.

Keywords:steel fiber reinforced ultra high strength concrete; direct shear test; shear strength; ductility

*天津市科技支撑计划项目（14ZCZDSF00016），国家科技支撑计划项目（2012BAJ07B05）。

作者简介：赵永娇，硕士，Email: 1143892713@qq.com。