纤维对混凝土的损伤、裂缝曲折度及裂缝恢复的影响

丁一宁; 李林泽; 曾伟

doi:10.13801/j.cnki.fhclxb.20181218.003

纤维对混凝土的损伤、裂缝曲折度及裂缝恢复的影响

大连理工大学海岸与近海工程国家重点实验室, 大连 116024

基金项目: 国家自然科学基金（51578109）

详细信息

通讯作者:
丁一宁,博士,教授,博士生导师,研究方向为高性能混凝土,E-mail:ynding@hotmail.com

中图分类号: TU528.572
计量
- 文章访问数: 818
- HTML全文浏览量: 69
- PDF下载量: 135
出版历程
- 收稿日期: 2018-10-17
- 刊出日期: 2019-10-14

Fibers effects on the concrete damage, crack tortuosity andcrack recovery

State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China

摘要

摘要: 通过混凝土圆饼劈裂试验预制准确宽度的裂缝，研究了钢纤维（SF）、聚丙烯（PP）长纤维对荷载作用下混凝土的损伤、裂缝曲折度及裂缝恢复率的影响。使用数码显微镜（Supereyes）和Image Pro Plus图像处理软件对不同位置裂缝实际宽度进行测量。通过测量劈拉作用下穿过圆饼试件的超声波速，分析、对比了各组试件超声波速与裂缝宽度、损伤变量因子之间的关系。研究表明：纤维的桥接作用使裂缝扩展得以控制，同时提高了卸载时的裂缝恢复程度和裂缝曲折度。SF掺量为55 kg/m³的混凝土试件比SF掺量为25 kg/m³的混凝土试件，曲折度增加26.9%，混杂使用PP长纤维和SF对提高混凝土裂缝表面曲折度有显著的正混杂效应。桥接于裂缝处的SF有利于超声波的传播，减缓超声波速损失。超声波速随着裂缝宽度的增加而逐渐降低、且与裂缝之间存在较好的指数关系，可用于表征混凝土内部裂缝的扩展。
- 纤维 /
- 超声波 /
- 劈裂试验 /
- 曲折度 /
- 裂缝恢复
Abstract: Through the disc splitting testing, the exact crack width of concrete has been prefabricated. In this work, the effects of steel fiber(SF) and macro polypropylene(PP) fiber on tortuosity, recovery rate and damage of concrete cracks were studied. The crack widths at different locations were measured using the digital microscope (Supereyes) and Image Pro Plus (an image processing software). In order to analyze the relationship between ultrasonic velocity and crack width as well as damage variable factors of different specimens, the ultrasonic velocity passing through the concrete disc under splitting load was also measured. The experimental results show that the crack widening can be controlled by the fiber bridging effect, and the crack recovery and tortuosity of crack can be increased simultaneously. Compared with the concrete sample with a SF content of 25 kg/m³, the crack tortuosity of the sample with a SF content of 55 kg/m³ increases by 26.9%; the hybrid use of macro PP fibers and SF indicates significant positive hybrid effect on the increasing of crack surface tortuosity. The steel fibers acrossing the cracks may improve the propagation of ultrasonic wave and decline the loss of the ultrasonic velocity. The ultrasonic velocity may decrease with the increasing of the crack width, and there is an exponential relationship between the crack width and ultrasonic velocity, which can be used to illustrate the crack development of concrete matrix.
- fiber /
- ultrasonic /
- splitting testing /
- tortuosity /
- crack recovery

HTML全文

参考文献(0)

施引文献(10)

期刊类型引用(6)

1.	郑蔚，刘大翔，张琳瑶，杨悦舒，丁瑜，夏栋，肖海，许文年. 不同类型外掺料对植被混凝土抗冻性能的影响. 金属矿山. 2025(01): 300-308 . 百度学术
2.	罗滔，李骄洋，张天祺，金峰. 基于DIC技术的自密实混凝土界面裂缝扩展规律研究. 水资源与水工程学报. 2024(01): 143-153 . 百度学术
3.	徐佳慧，杨予，刘恒，周强兵. 泊松比变化对基于波速混凝土损伤计算的影响. 计量学报. 2024(06): 881-889 . 百度学术
4.	乔雪涛，王朋，闫存富，许华威，张力斌，贾克，杨泽，吴隆. 钢-聚丙烯纤维增强人造花岗岩复合材料的制备与性能. 复合材料学报. 2020(08): 1823-1831 . 本站查看
5.	曾伟，丁一宁. 荷载作用下结构型纤维对混凝土裂缝渗透率演化的影响. 复合材料学报. 2020(09): 2314-2323 . 本站查看
6.	丁一宁，马跃，郝晓卫. 基于分形理论分析裂缝形态对纤维/混凝土渗透性的影响. 复合材料学报. 2020(11): 2908-2916 . 本站查看