毛细吸水作用对水泥砂浆电阻率的影响研究  

Influence of Capillary Water Absorption on Resistivity of Cement Mortar

作　　者：曾晓辉[1] 凌晨博 潘璋 王平[1] 李鲲鹏[2,3] 罗信伟[3] 崖尚松 ZENG Xiaohui;LING Chenbo;PAN Zhang;WANG Ping;LI Kunpeng;LUO Xinwei;YA Shangsong(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;School of Electrical Engineering,Southwest Jiaotong University,Chengdu 610031,China;Guangzhou Metro and Design Research Institute Co.,Ltd.,Guangzhou 510010,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]西南交通大学电气工程学院,四川成都610031 [3]广州地铁设计研究院有限公司,广东广州510010

出　　处：《建筑材料学报》2018年第5期714-719,共6页Journal of Building Materials

基　　金："十三五"国家重点研发计划(2016YFB0303603-4)

摘　　要：采用四电极法测定了水泥砂浆电阻率随毛细吸水时间的变化,并分析了水灰比、聚合物乳液、引气剂对其变化的影响.研究表明:随毛细吸水时间的增加,水泥砂浆电阻率先缓慢降低,随后迅速下降,最后保持稳定;毛细吸水可使水泥砂浆电阻率降低70%以上,这可能与吸水后砂浆内部形成的孔隙导电通道有关;增大水灰比和掺入引气剂均可大幅度提高干燥条件下砂浆的电阻率,且对吸水状态下砂浆的电阻率也有一定提高作用,但对吸水后砂浆的电阻率影响不大;6%聚合物乳液掺量(聚合物的固含量占水泥质量的百分数)不仅可提高干燥条件下的砂浆电阻率,也可提高吸水后的砂浆电阻率(提高4倍左右,且保持在360Ω·m以上),原因可能与水灰比、聚合物乳液、引气剂对砂浆毛细孔隙结构的影响有关.The influence of water-cement ratio,polymer emulsion and air entraining agent on the change of cement mortar resistivity with capillary water absorption time was studied by four-electrode method.The study shows that with the increase of capillary suction time,the resistivity of cement mortar is lowered down,then decreases rapidly,then remains stable;capillary suction can make the resistivity of cement mortar decrease by more than 70%,which may be related to the pore water after the mortar is formed inside the conductive channel;increasing the water-cement ratio and mixing air entraining agent can greatly improve the resistivity of mortar under drying condition,and also have a certain effect on the resistivity of mortar under the condition of water absorption,but have little effect on the resistivity of mortar after water absorption,and the incorporation of 6%polymer emulsion can not only improve the resistivity of dry conditions,but also improve the resistivity of mortar after absorbing water(up to about 4 times,and higher than 360Ω·m),these may be related to the effect of the water-cement ratio,polymer emulsion,air entraining agent on capillary pore structure of mortar.

关 键 词：毛细吸水作用 水泥砂浆 电阻率 四电极法 孔隙结构 

分 类 号：TQ172.1[化学工程—水泥工业]