混杂纤维超高性能混凝土的弯曲力学性能研究  

Flexural property of fiber-doped ultra-high performance concrete

作　　者：聂立力 周迅 熊伟 NIE Lili;ZHOU Xun;XIONG Wei(Central&Southern China Municipal Engineering Design and Research Institute Co.,Ltd,Wuhan 430010,China)

机构地区：[1]中国市政工程中南设计研究总院有限公司,湖北武汉430010

出　　处：《武汉工程大学学报》2024年第3期330-336,共7页Journal of Wuhan Institute of Technology

基　　金：湖北省建设科技计划项目(2023011)。

摘　　要：通过超高性能混凝土(UHPC)棱柱体的四点弯曲试验,研究了4种纤维掺量的长直型、端钩型和混合型钢纤维UHPC的弯拉性能,并与倒推分析法得到的UHPC拉伸性能进行对比。结果表明:纤维类型和纤维掺量对UHPC棱柱体弯拉性能的弹性阶段无明显影响,其影响主要作用在裂缝发展阶段;混合型纤维UHPC对弯拉性能的裂缝发展阶段改良效果最优,且混合型纤维提供的抗力效果较其他类型纤维更优。倒推分析法的初裂强度高于轴拉等效初裂强度,两者比值介于1.03~1.19。Flexural properties of long straight,hooked end,and hybrid steel fiber ultra-high performance concrete(UHPC)with four different fiber contents were investigated by four-point bending tests of UHPC prisms.The results were compared to the tensile properties of UHPC obtained using an inverse analysis method.It was found that fiber type and content had a minimal impact on the elastic stage of UHPC prism flexural properties but significantly affected the post-crack stage.The hybrid fiber UHPC showed the most optimal reinforcement effect on the post-crack stage,with hybrid fibers exhibiting superior resistance compared to other fiber types.The cracking strength determined by the inverse analysis method was higher than the direct-tension equivalent cracking strength,with a ratio ranging from 1.03 to 1.19.

关 键 词：超高性能混凝土 四点弯曲试验 倒推分析法 初裂强度 极限强度 

分 类 号：U444[建筑科学—桥梁与隧道工程]