摘要
本文通过对不同水灰比和粉煤灰掺量的6个配比的聚乙烯醇纤维增强水泥基复合材料单轴拉伸试验,研究了各配比试件的应力-应变关系及抗拉特征参数。试件采用150mm×75mm×15mm的长方形试块。至位移控制的拉伸试验机上进行拉伸试验,测定应力-应变完整曲线。试验结果表明,高韧性纤维增强水泥基复合材料在拉伸荷载下应力-应变关系可分为弹性上升阶段、应变硬化阶段和应变软化阶段。在所选取的材料及配比范围内,在单轴拉伸荷载下均能实现应变硬化与多重开裂,极限拉应变的最大值可达1.7%,最小和最大临界裂纹宽度分别为26μm和90μm。
The stress-strain relationship and tensile resistance parameters of polyvinyl alcohol （PVA） fiber reinforced cementitious composite were studied experimentally by uni-axial tensile test. The specimens were 150mm×75mm×15mm with different water to cement ratios and fly ash quantities. The test was carried out by using displacement controlled test installation and complete stress-strain curves were obtained. The results show that the stress-strain curve can be divided into three periods： 1. elastic period, in which the strain is linearly proportional to stress; 2. strain hardening period, in which cracking occurs and the ratio of stress increment to strain increment is much lower than that in elastic period; 3. strain softening period, in which the cracks begin to propagate. The analysis of test data indicates that in the range of mix adopted in this experimental study, the pseudo-strain hardening and multiple cracking performances can be realized. The ultimate tensile strain is 1.7 %, and the minimum and maximum crack widths are 26μm and 90μm respectively.
出处
《水利学报》
EI
CSCD
北大核心
2008年第3期361-366,共6页
Journal of Hydraulic Engineering
关键词
纤维增强水泥基复合材料
单轴拉伸
抗拉应变
裂纹宽度
fiber reinforced
cementitious composite
uniaxial tensile performance
strain
crack width
