建筑结构学报2024，Vol.45Issue(9)：13-28,16.DOI:10.14006/j.jzjgxb.2023.0615
钢纤维掺量和配筋率对UHPC轴拉性能和开裂行为的影响
Effect of steel fiber content and reinforcement ratio on tensile properties and cracking behavior of UHPC
摘要
Abstract
Ultra-high performance concrete(UHPC)is widely used as a reinforcing or protective layer for structures due to its excellent physical and mechanical properties,but the high cost due to typical fiber content of 2％ to 3％ hinders its further application.Compared to UHPC with typical fiber content,UHPC with low fiber content has a lower material cost and has the potential to improve the ductility of reinforced UHPC.To understand fully the tensile mechanical properties and cracking behavior of rebar-reinforced UHPC with low fiber content and to evaluate the effect of changing the reinforcement ratio,in this paper,the tensile responses of a total of 30 specimens in 10 groups were tested by direct tensile tests,the effects of reinforcement ratio and fiber content on the ductility,tensile load-bearing capacity,and cracking behavior of the reinforced UHPC were analyzed,and the characteristics of fiber distribution inside the specimens were quantitatively evaluated based on the image recognition.The results show that the ductility of UHPC with 0.5％ fiber content increases approximately linearly with the increase of reinforcement ratio,but altering the reinforcement ratio has a limited effect on the ductility of UHPC with 2.0％ fiber content.When the reinforced UHPC reaches the tensile load-bearing capacity,the stresses of UHPC and steel rebar are affected by the combination of reinforcement ratio and fiber content,which need to be considered when calculating the tensile load-bearing capacity.Adding rebars significantly improves the ability of UHPC with 0.5％ fiber content to control the maximum crack width,but has no significant effect on the ability of UHPC with 2.0％ fiber content to control maximum crack width.Changing the reinforcement ratio has less effect on the maximum crack width of reinforced UHPC.After reducing the fiber content from 2.0％ to 0.5％,the other axial tensile properties of the reinforced UHPC are not basically degraded,except for a slight reduction in the ability to control the maximum crack width.关键词
超高性能混凝土/钢纤维掺量/配筋率/纤维分布/轴拉试验/数字图像相关方法/轴拉性能/开裂行为Key words
ultra-high performance concrete(UHPC)/fiber content/reinforcement ratio/fiber distribution/axial tensile test/digital image correlation(DIC)method/tensile property/cracking behavior分类
建筑与水利引用本文复制引用
罗贤志,张素梅,李爱东,张晨明,赵林,张雨晨..钢纤维掺量和配筋率对UHPC轴拉性能和开裂行为的影响[J].建筑结构学报,2024,45(9):13-28,16.基金项目
国家自然科学基金项目(52178130),"十四五"国家重点研发计划项目(2022YFC3802001),中国铁路设计集团有限公司科技项目(2018-029). （52178130）
