盐冻作用下掺粉煤灰水工混凝土性能演化试验研究  

Experimental Study on Performance Evolution of Hydraulic Concrete Mixed with Fly Ash under Salt Freezing

作　　者：刘泽峰 乔雨 LIU Zefeng;QIAO Yu(PowerChina Water Environment Governance, Shenzhen 518102, China;China Three Gorges Construction Management Co., Ltd, Chengdu 610000, China)

机构地区：[1]中电建水环境治理技术有限公司,广东深圳518102 [2]中国三峡建设管理有限公司,四川成都610000

出　　处：《人民珠江》2018年第12期103-107,共5页Pearl River

摘　　要：开展盐冻(5%Na2SO4)作用下湿筛混凝土的试验,定量分析了试块的质量损失、相对动弹性模量、抗压强度随冻融循环次数的变化。结果表明:随着粉煤灰掺量的增加,盐冻作用下湿筛混凝土试件的质量损失、相对动弹性模量、抗压强度明显高于水冻作用下,且冻融后期呈指数式迅速下降,相对动弹性模量和抗压强度大致呈线性关系,并依据试验数据建立了二者的函数关系式。依据抗压强度损失率≥50%,推导出掺粉煤灰混凝土新的冻融评价标准:相对动弹性模量≤72%,为运用相对动弹性模量指标来精确评价盐冻作用下掺粉煤灰湿筛混凝土的损伤性能提供了理论依据。By carrying out the experiments of wet sieving concrete under the action of salt freezing(5%Na2SO4),the mass loss,the relative dynamic elastic modulus and the compressive strength of the test block with the change of the number of freeze-thaw cycles are quantitatively analyzed.The results show that the mass loss,relative dynamic elastic modulus and compressive strength of wet sieving concrete specimens under salt freezing are significantly higher than those under water freezing with the increase of fly ash content.and they drop rapidly in an exponential way in the late freeze-thaw period.At the same time the relative dynamic elastic modulus and compressive strength are approximately linear.And a functional relationship between the two is established based on experimental data.According to that the loss rate of compressive strength is≥50%,a new freeze-thaw evaluation standard for fly ash concrete was deduced:the relative dynamic elastic modulus was≤72%,which provides the theoretical basis for using and the relative dynamic modulus of elasticity to accurately evaluate the damage performance of wet sieving concrete mixed with fly ash under salt freezing.

关 键 词：盐冻 相对动弹性模量 抗压强度 粉煤灰掺量 湿筛混凝土 

分 类 号：TV431[水利工程—水工结构工程]