混杂纤维对海水珊瑚砂ECC力学性能的影响  

Effect of hybrid fibers on the mechanical properties of seawater corals and ECC

作　　者：章雨 宫能平[1] 苏鹏 钟美婷 穆朝民[1] ZHANG Yu;GONG Nengping;SU Peng;ZHONG Meiting;MU Chaomin(Anhui University of Science and Technology)

机构地区：[1]安徽理工大学

出　　处：《防护工程》2024年第3期7-15,共9页Protective Engineering

基　　金：国家重点研发计划课题(2021YFC3100802)

摘　　要：采用珊瑚砂、人工海水和纤维等原材料制备海水珊瑚砂高延性纤维增强水泥基复合材料(SCECC)。试验研究了混杂纤维对SCECC抗压、劈裂抗拉力学性能的影响,并利用数字图像相关技术(DIC)对SCECC试件在压缩过程中应变场演化及裂缝扩展进行分析。结果表明:通过聚乙烯醇(PVA)纤维替代部分钢纤维(SF),随着替代量的增加,试件的抗压强度逐渐降低,抗拉强度呈现先增后减的趋势,聚丙烯(PP)纤维替代部分SF也有类似结论;混杂纤维SCECC试件的峰值应变均高于对照组和单掺SF试件的峰值应变,且应力-应变曲线下降段更为平缓;通过DIC获取试件在受压过程中的应变演化云图,观察到混杂纤维减少了SCECC试件的应力集中现象,提高了SCECC抵抗变形破坏的能力;综合力学性能和DIC分析,在SF掺量(体积掺量)为1.5%,PVA掺量为0.5%时,SCECC试件具有更优异的性能。Raw materials such as coral sand,artificial seawater,and fibers were used to prepare seawater corals and engineered cementitious composite(SCECC).The effects of hybrid fibers on the compressive and splitting tensile strength properties of SCECC were experimentally investigated,and the strain field evolution and crack extension of SCECC specimens during compression were analyzed using digital image correlation(DIC)technology.The results show that by replacing some steel fibers(SF)by polyvinyl alcohol(PVA)fibers,the compressive strength of the specimens gradually decreases and the tensile strength shows a tendency to increase and then decrease with the increase of the replacement amount,and similar conclusions are found in the case of replacing some SF by polypropylene(PP)fibers.The peak strain of the hybrid fiber SCECC is higher than that of the control group and the SF-doped specimen,and the decrease of the stress-strain curve is more gentle.The strain evolution cloud diagram of the specimen during compression was obtained by DIC.It was observed that the hybrid fiber reduced the stress concentration of the SCECC specimen and improved the ability of SCECC to resist deformation and failure.Based on the comprehensive mechanical properties and DIC analysis,SCECC specimens have better performance when the SF content(volume content,the same below)is 1.5%and the PVA content is 0.5%.

关 键 词：高延性纤维增强水泥基复合材料 珊瑚砂 力学性能 混杂纤维 数字图像相关技术 

分 类 号：P75[天文地球—海洋科学] TU528[建筑科学—建筑技术科学]