【作者】 杨富花； 石宵爽； 栾晨晨； 张宽裕； 代金芯； 王清远；

【Author】 YANG Fuhua;SHI Xiaoshuang;LUAN Chenchen;ZHANG Kuanyu;DAI Jinxin;WANG Qingyuan;Key Laboratory of Deep Underground Science and Engineering,Ministry of Education,College of Architecture and Environment,Sichuan University;Failure Mechanics and Engineering Disaster Prevention and Mitigation Key Lab of Sichuan Province,College of Architecture and Environment,Sichuan University;College of Mechanical Engineering,Chengdu University;

【机构】 深地科学与工程教育部重点实验室四川大学建筑与环境学院； 破坏力学与工程防灾减灾四川省重点实验室四川大学建筑与环境学院； 成都大学机械工程学院；

【摘要】 聚甲醛(polyoxymethylene,POM)纤维具有高强度、高模量及优良的尺寸稳定性、热稳定性和耐碱腐蚀、耐化学腐蚀、耐光、耐磨损等性能,是一种综合性能优异的有机合成纤维。研究发现POM纤维对地聚物再生混凝土(Geopolymer recycled concrete,GRC)的力学性能的增强效果显著。为进一步研究POM纤维对GRC的增强增韧作用,本文通过扫描电镜(SEM)和X射线能谱分析(EDS)对不同POM纤维体积掺量的GRC进行了微观结构观测,根据纤维间距理论、复合材料理论及纤维混凝土损伤理论对其增韧机理进行了分析。结果表明:POM纤维在GRC中分布均匀,形成无规则网状结构,通过桥联搭接作用增强了GRC的力学性能;当GRC试件受力破坏时,POM纤维的断裂、拨出和剥离行为分散和吸收了裂纹处的断裂能,可以有效阻止裂纹继续扩张;POM纤维没有与地聚物发生反应生成新的物质。更多还原

【Abstract】 Polyoxymethylene(POM) fiber has high strength,high modulus,excellent dimensional stability,thermal stability and alkali corrosion resistance,chemical corrosion resistance,light resistance and abrasion resistance.It is an organic synthetic fiber with excellent comprehensive properties.It is found that POM fiber can significantly enhance the mechanical properties of geopolymer recycled concrete(GRC).In order to further study the strengthening and toughening effect of POM fiber on GRC,the microstructure of GRC with different POM fiber volume content was observed by scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDS),and the toughening mechanism was analyzed according to the fiber spacing theory,composite material theory and fiber reinforced concrete damage theory.The results show that:POM fibers are evenly distributed in GRC,forming irregular network structure,and the mechanical properties of GRC are enhanced by bridging action;when GRC specimens are damaged under stress,the fracture,pull-out and stripping behaviors of POM fiber disperse and absorb the fracture energy at the crack,which can effectively prevent the crack from expanding;POM fiber didn’t react with geopolymer to form new substances.更多还原