摘要
将聚乙烯醇纤维(PVA纤维)以不同体积掺量(0、0.1%、0.2%、0.3%)掺入混凝土中,开展PVA纤维混凝土试件在不同浓度复合盐溶液(Na_(2)SO_(4)+NaCL)浸泡与烘干作用下的宏-微观腐蚀劣化试验,探究南疆极端干旱盐渍土环境下PVA纤维混凝土的抗盐蚀性能。结果表明:(1)PVA纤维在混凝土内部的拉结作用降低了试件表面砂浆层的剥蚀速率,减少了试件表层裂缝及孔洞的生成数量。(2)PVA纤维的掺入提高了混凝土抵抗复合盐侵蚀的能力,随着复合盐溶液浓度的增大,纤维掺量为0.3%试件的相对动弹性模量和质量损失率波动幅度最小,其宏观耐久性能表现最稳定。(3)复合盐溶液侵蚀下,PVA纤维混凝土发生物理腐蚀和化学腐蚀破坏,产物主要是钙矾石(AFt)和石膏,并且纤维的掺入减少了腐蚀产物的生成量,这与试件宏观耐久性能评价指标的变化规律具有一致性。研究成果可为PVA纤维混凝土在南疆盐渍土地区实际工程中的应用提供参考依据。
Polyvinyl alcohol fiber(PVA fiber)was mixed into concrete with different volume content(0,0.1%,0.2%,0.3%),and themacro and microcorrosion degradation tests of concrete specimens with PVA fiber were carried out,under the action of soaking and drying in different concentrations of compound salt solution(Na_(2)SO_(4)+NaCl),to explore the salt corrosion resistance of PVA fiber concrete in extremely arid saline soil environment in Southern Xinjiang.The salt corrosion resistance of PVA fiber concrete under extreme arid saline soil environment in Southern Xinjiang was investigated.The results show that(1)The tie-reinforcement effect of PVA fiber in concrete reduces the erosion rate of mortar layer and the number of cracks and holes on the surface of specimens.(2)The addition of PVA fiber improves the resistance of concrete to compound salt erosion.With the increase of compound salt solution concentration,the relative dynamic elastic modulus and mass loss rate of specimens with PVA fiber content of 0.3% achieves the minimum value,which indicate that its macroscopic durability performance is the most stable.(3)Under the compound salt solution erosion,some physical corrosion and chemical corrosion failure occur in PVA fiber concrete,and the products are mainly ettringite(AFt)and gypsum,and the addition of fiber reduces the amount of corrosion products,which is consistent with the variation rule of the evaluation indexes for the macroscopical durability of specimens.The results can provide a reference for the application of PVA fiber concrete in the saline soil area of Southern Xinjiang.
作者
王成
戎泽斌
葛广华
李曦彤
李桢怡
薛山
WANG Cheng;RONG Zebin;GE Guanghua;LI Xitong;LI Zhenyi;XUE Shan(College of Water Resources and Architectural Engineering,Tarim University,Alar 843300,China;South Xinjiang Geotechnical Engineering Research Center,Tarim University,Alar 843300,China)
出处
《混凝土》
CAS
北大核心
2022年第9期82-88,共7页
Concrete
基金
国家自然科学基金项目(52168035)
新疆生产建设兵团区域创新引导计划项目(2018BB045)
新疆生产建设兵团重点领域科技攻关计划项目(2019AB016)。
关键词
聚乙烯醇纤维混凝土
复合盐溶液
干湿循环
耐久性能
微观特征
polyvinylalcohol fiber concrete
compound salt solution
wet and dry cycle
durability
microscopic characteristics
