无机增殖剂对PE/ECC力学、抗氯离子渗透及自愈合性能的影响
Effect of capillary crystalline cement additive on the mechanical,anti-chloride ion permeability,and self-healing properties of PE/ECC
谭燕 1龙雄 1余江滔 2赵犇1
作者信息
- 1. 湖北工业大学 土木建筑与环境学院,武汉 430068
- 2. 同济大学 土木工程学院,上海 200092
- 折叠
摘要
为研究无机增殖剂(CCCA)对聚乙烯(PE)纤维增强高延性水泥基复合材料(ECC)力学、抗氯离子渗透及自愈合性能的影响,以PE/ECC为对照组,分别掺入不同质量分数的CCCA(2wt%、4wt%、6wt%、8wt%、10wt%),通过抗压、抗折、抗拉、电通量法及预加应变损伤法对PE/ECC力学、抗氯离子渗透及自愈合性能进行研究,并利用XRD、SEM-EDS对其自愈合产物进行物相成分、微观形貌及元素组成分析.结果表明:随着CCCA掺量的增加,PE/ECC力学和抗氯离子渗透性能呈先增后减趋势,当CCCA掺量为 4wt%时,CCCA对PE/ECC力学和抗氯离子渗透性能整体提升最为明显,抗压、抗折、极限抗拉强度分别提升了55.5%、10.8%、79.4%,极限拉应变变化不大,电通量下降了 38.6%.自愈合试验表明,掺入CCCA后,PE/ECC抗拉强度和应变能的恢复率有明显提升,自愈合性能得到了增强.当预损伤应变为 0.5%时,掺CCCA的PE/ECC试件抗拉强度和应变能在养护 84天后均高于原始基体,较原始基体分别提高 10.41%和2.83%.未掺CCCA的PE/ECC试件在 3种应变损伤下的抗拉强度和应变能均低于原始基体.XRD和SEM-EDS结果显示,掺CCCA的PE/ECC水化产物中CaCO3、水化硅酸钙(C-S-H)、钙矾石(AFt)衍射峰值强度有所增长,自愈合产物主要是C-S-H晶体,且掺CCCA的PE/ECC中分布更密集.
Abstract
To study the effects of capillary crystalline cement additive(CCCA)on the mechanical,chloride ion penetration resistance and self-healing properties of polyethylene(PE)fiber reinforced engineered cementitious composites(ECC),PE/ECC was used as the control group and mixed with different mass fractions of CCCA(2wt%,4wt%,6wt%,8wt%,10wt%),and the mechanical,anti-chloride ion permeability and self-healing properties of PE/ECC were investigated by compressive,flexural,tensile,electric flux method and pre-loaded strain damage method,and the self-healing products were analyzed by XRD and SEM-EDS for their physical composition,micro-scopic morphology and elemental composition.The results show that:The mechanical and anti-chloride ion per-meability of PE/ECC increase and then decrease with the increase of CCCA doping,and when the doping of CCCA is 4wt%,the mechanical and anti-chloride ion permeability of PE/ECC is most obviously improved by CCCA,and the compressive strength,flexural strength and ultimate tensile stress increase by 55.5%,10.8%,and 79.4%,respectively.The ultimate tensile strain does not change much,and the electrical flux decreases by 38.6%.The self-healing test shows that the recovery rate of tensile strength and strain energy of PE/ECC is significantly improved after doping with CCCA,and the self-healing performance is enhanced.When the pre-damage strain is 0.5%,the tensile strength and strain energy of PE/ECC specimens doped with CCCA are higher than those of the original matrix after 84 days of maintenance,which are 10.41%and 2.83%higher than those of the original matrix,respectively.The tensile strength and strain energy of PE/ECC specimens without CCCA are lower than those of undamaged specimens under three strain damages.The XRD and SEM-EDS results show that the CaCO3,calcium silicate hydrate(C-S-H),and ettringite(AFt)intensity diffraction peaks increase in the hydration products of PE/ECC with CCCA,and the self-healing products are mainly C-S-H crystals,and the distribution is denser in the PE/ECC with CCCA.
关键词
无机增殖剂/水泥基复合材料/抗氯离子渗透性能/自愈合/微观形貌Key words
capillary crystalline cement additive/engineered cementitious composites/anti-chloride ion per-meability/self-healing/microscopic morphology引用本文复制引用
出版年
2024
NETL
NSTL
万方数据