云母含量对泵送山砂混凝土抗压强度的影响  

Effect of Mica Content on Compressive Strength of Pumping Rock Sand Concrete

作　　者：高礼雄 谭文君 张彦 李红辉 GAO Lixiong;TAN Wenjun;ZHANG Yan;LI Honghui(School of Materials Science and Engineering, Shijiazhuang Tiedao University, Shijiazhuang 050043, China;Guangdong Changda Test Engineering Development Co. Ltd., Guangzhou 511431, China)

机构地区：[1]石家庄铁道大学材料科学与工程学院,河北石家庄050043 [2]广东长大试验技术开发有限公司,广东广州511431

出　　处：《国防交通工程与技术》2021年第4期60-63,共4页Traffic Engineering and Technology for National Defence

摘　　要：通过云母等质量替代山砂方式,探究了云母含量对不同强度等级泵送山砂混凝土抗压强度的影响,并通过X射线衍射和压汞测试手段,分析了水泥石的物相组成和孔结构变化。结果表明:云母含量对泵送山砂混凝土抗压强度的不利影响与混凝土强度等级有关。为降低云母含量带来的不利影响,C40及以下混凝土强度要求云母最高含量应小于2%,C50混凝土强度要求云母最高含量应小于1%。当云母含量超出适宜范围达3%时,通过降低水胶比方式已不能改善云母含量对混凝土强度的不利影响,这主要是由于云母吸水形成的“水囊”在硬化水泥石中形成大量孔隙造成的。By replacing rock sand with equal mass mica,the research explored the influence of mica content on the compressive strength of pumping rock sand concrete with different strength grades.Using X-ray diffraction(XRD)and mercury intrusion porosimetry(MIP)testing techniques,the phase composition and pore structure changes of cement paste were analyzed.The results show that the adverse effect of mica content on the compressive strength of pumping rock sand concrete is related to the concrete strength grade.In order to reduce the adverse effect of mica content,C40 or below concrete strength requires that the maximum mica content should be less than 2%,and C50 concrete strength requires that the maximum mica content should be less than 1%.When the mica content exceeds the appropriate range up to 3%,the adverse effect of the mica content on the strength of concrete cannot be improved by reducing the water-binder ratio,which is mainly caused by the formation of a large number of pores in the hardened cement paste due to the"water pocket"formed by the absorption of water by mica.

关 键 词：山砂混凝土 云母含量 抗压强度 泵送 微观结构 

分 类 号：TU528[建筑科学—建筑技术科学]