铁尾矿掺量对冻融循环和硫酸盐侵蚀联合作用下混凝土抗劣化性能的影响  

Effect of Iron Tailings Content on the Anti-deterioration Performance of Concrete under theCombined Action of Freeze-thaw Cycles and Sulfate Corrosion

作　　者：陈跃余[1] 郭海燕 CHEN Yueyu;GUO Haiyan(Department of Civil Engineering,Neijiang Vocational and Technical College,Neijiang 641000,China;School of Civil Engineering,Sichuan University of Light and Chemical Technology,Chengdu 643000,China)

机构地区：[1]内江职业技术学院土木工程系,四川内江641000 [2]四川轻化工大学土木工程学院,四川成都643000

出　　处：《金属矿山》2023年第7期296-300,共5页Metal Mine

基　　金：四川省教育厅自然科学项目(编号:18ZC0329)。

摘　　要：为研究铁尾矿掺量在硫酸钠冻融循环作用下的混凝土劣化机理,对铁尾矿混凝土的质量和抗压强度损失率、相对动弹性模量进行了测试,建立了基于威布尔分布的冻融损伤模型。结果表明:硫酸钠冻融150次后,当铁尾矿的替代率为60%时,铁尾矿混凝土的质量损失最大,为1.7%;铁尾矿混凝土的抗压强度损失率随着冻融次数增加不断增大;60次冻融后,IC15组铁尾矿混凝土和IC45组铁尾矿混凝土的抗压强度损失率明显低于普通混凝土;IC30组铁尾矿混凝土的相对动弹性模量损失最小,而IC60组铁尾矿混凝土的相对动弹性模量损失最大。冻融循环0~30次时,相对动弹性模量降低缓慢,损失较小,当铁尾矿替代率为30%时,相对动弹性模量损失最小,抗冻性和抗硫酸盐侵蚀性最佳;铁尾矿混凝土在冻融循环与硫酸盐侵蚀联合作用下的冻融损伤模型符合威布尔分布,相关系数R2大于0.96。In order to study the deterioration mechanism of concrete under the freeze-thaw cycle of sodium sulfate,the loss rate of mass,compressive strength and relative dynamic elastic modulus of iron tailings concrete were tested,and a freezethaw damage model based on Weibull distribution was established.The results show that when the replacement rate of iron tailings is 60%,the quality loss of iron tailings concrete is 1.7%after 150 freeze-thaw times.The compressive strength loss rate of iron tailings concrete increases with the increase of freezing and thawing times.After 60 freeze-thaw cycles,the compressive strength loss rate of IC15 iron tailings concrete and IC45 iron tailings concrete is significantly lower than that of ordinary concrete.The relative dynamic elastic modulus loss of IC30 group iron tailings concrete is the smallest,while the relative dynamic elastic modulus loss of IC60 group iron tailings concrete is the largest.When the freeze-thaw cycle is 0~30 times,the relative dynamic elastic modulus decreases slowly and the loss is small.When the replacement rate of iron tailings is 30%,the relative dynamic elastic modulus loses the least,and the freeze resistance and sulfate resistance are the best.The freeze-thaw damage model of iron tailings concrete under the combined action of freeze-thaw cycle and sulfate erosion accords with Weibull distribution,and the correlation coefficient R2 is greater than 0.96.

关 键 词：铁尾矿 硫酸钠 冻融循环 质量损失率 抗压强度损失率 冻融损伤模型 

分 类 号：TD981[矿业工程—选矿] TU528[建筑科学—建筑技术科学]