混杂纤维风积沙混凝土抗冻性研究及寿命预测  

Study on frost resistance and life prediction of hybrid fiber aeolian sand concrete

作　　者：李昊[1] 周一 张园[2] 郭皓隆 郭汝阳 韩秋硕 LI Hao;ZHOU Yi;ZHANG Yuan;GUO Haolong;GUO Ruyang;HAN Qiushuo(College of Water Conservancy and Civil Engineering,Inner Mongolia Agricultural University,Hohhot,Inner Mongolia 010018,China;School of Modern Service and Management,Inner Mongolia Technical College of Construction,Hohhot,Inner Mongolia 010070,China)

机构地区：[1]内蒙古农业大学水利与土木建筑工程学院,内蒙古呼和浩特010018 [2]内蒙古建筑职业技术学院现代服务与管理学院,内蒙古呼和浩特010070

出　　处：《排灌机械工程学报》2025年第3期275-283,共9页Journal of Drainage and Irrigation Machinery Engineering

基　　金：内蒙古自然科学基金资助项目(2021MS05045);鄂尔多斯市科技重大专项(2022EEDSKJZDZX014);内蒙古自治区硕士研究生科研创新项目(S20231121Z)。

摘　　要：为探究内蒙古盐碱区建构筑物遭受冻融循环的侵蚀特点,以风积沙混凝土(ASC)作为基准组,以复掺一定比例碳酸钙晶须和聚丙烯纤维的风积沙混凝土(HF4)作为试验组,采用不同质量浓度的氯盐溶液作为侵蚀溶液,利用快冻法模拟野外服役环境,借助扫描电子显微镜(SEM)对冻融后试件的微观形貌进行观测,运用核磁共振(NMR)探究孔隙结构变化,最后采用Weibull函数建立耐久性退化模型预测试件寿命.结果表明:随着冻融循环的持续进行,混凝土表面浆体逐渐剥落,质量和相对动弹性模量损失严重,无害孔和少害孔演变为有害孔和多害孔,加速混凝土的冻胀破坏.混掺纤维有助于改善混凝土内部微观结构,显著提高ASC抗冻性.通过Weibull函数建立混凝土在冻融作用下寿命预测模型,计算得出HF4在同种环境下安全服役期较ASC最大可提高36.8%.In order to explore the erosion characteristics of buildings subjected to freeze-thaw cycles in the saline-alkali area of Inner Mongolia,the aeolian sand concrete(ASC)was used as the reference group,and the aeolian sand concrete(HF4)mixed with a certain proportion of calcium carbonate whiskers and polypropylene fibers was used as the test group.Different concentrations of chloride salt solution were used as erosion solution,and the field service environment was simulated by rapid free-zing method.The microstructure of the specimens after freeze-thaw was observed by scanning electron microscope(SEM),and the pore structure changes were explored by nuclear magnetic resonance(NMR).Finally,the Weibull function was used to establish the durability degradation model to predict the life of the specimens.The results show that with the continuous freeze-thaw cycle,the slurry on the surface of the concrete gradually peels off,the loss of mass and relative dynamic elastic modulus is serious,and the harmless holes and less harmful holes evolve into harmful holes and more harmful holes,which accelerates the frost heaving damage of the concrete.The mixed fiber helps to improve the internal microstructure of concrete and significantly improve the frost resistance of ASC.The life prediction model of concrete under freeze-thaw action is established by Weibull function.It is calculated that the safe service life of HF4 in the same environment can be increased by 36.8%compared with ASC.

关 键 词：碳酸钙晶须 聚丙烯纤维 风积沙混凝土 冻融循环 Weibull函数 

分 类 号：S277.9[农业科学—农业水土工程]