原料粒度对磷酸镁水泥水化硬化特性的影响  

Effects of particle size of starting materials on hydration and hardening process of magnesia-phosphate cement

作　　者：杨建明[1,2] 钱春香[1,3] 张青行 焦宝祥[2] 阎晓波[2] 

机构地区：[1]东南大学材料科学与工程学院,南京211189 [2]盐城工学院土木工程学院,盐城224051 [3]东南大学江苏省土木工程材料重点实验室,南京211189 [4]盐城市水利局,盐城224003

出　　处：《东南大学学报（自然科学版）》2010年第2期373-379,共7页Journal of Southeast University：Natural Science Edition

基　　金：江苏省高校自然科学基础研究面上项目(08KJ560004);住房和城乡建设部科学技术计划项目(2008-K4-35);江苏省水利科技重点资助项目(2006021);江苏省交通科学研究资助项目(08Y07-1)

摘　　要：研究了原料粒度对新型磷酸镁水泥(MPC)水化硬化过程的影响规律.首先,以一定量不同粒度的烧结氧化镁粉(MgO)和磷酸二氢钾(KH2PO4)搭配并掺入不同量的缓凝剂硼砂(Na2B4O7.10H2O)配制MPC.然后,测试MPC浆体3h内半绝热温升曲线、凝结时间和MPC硬化体的强度,并分析硬化体的物相组成和微观结构形貌.结果表明:MgO粉和KH2PO4的粒度对MPC水化硬化特性有显著影响,随着MgO粉和KH2PO4的颗粒粒径减小,早期水化反应速率加快,凝结时间缩短;但对于抗压强度并非颗粒越小其值越大,在最佳MgO粉和KH2PO4粒度范围内,MPC硬化体抗压强度最高.同样,对一定粒度MgO粉和KH2PO搭配的MPC浆体,在硼砂适量时,MPC硬化体才能具有适宜的凝结时间、水化反应速度和较高的抗压强度.The effects of the particle size of starting materials on the hydration and hardening process of magnesium-phosphate cement（MPC） are investigated by measuring the temperature rise within 3 h,setting time and compressive strength of MPC pastes.They are composed of certain amount of dead MgO powders and potassium phosphate（KH2PO4） with different particle sizes and different borax（Na2B4O7·10H2O） dosage.The hydration products and micrographs of the hardened MPC pastes are analyzed.The experimental results show that the particle size of dead MgO powers and KH2PO4 markedly affect the hydration and hardening process of MPC pastes.With the decrease of particle sizes of MgO powers and KH2PO4,the early hydration reaction rate of MPC paste accelerates obviously,and its setting time is shortened;however,the compressive strength of hardened MPC does not increase continuously with the decrease of the particle size of starting materials,and there exists an optimum particle size range of MgO powers and KH2PO4.With certain particle size of MgO powders and KH2PO4,there is also an optimum B dosage for the hardened MPC paste to have suitable setting time,temperate hydration rate and high compressive strength.

关 键 词：磷酸镁水泥(MPC) 粒度 凝结时间 强度 

分 类 号：TU528.31[建筑科学—建筑技术科学]