水泥-磷渣水化体系的缓凝现象及水化特性研究  

Investigation of retarding effect and hydration characteristics in cement-phosphorusslag hydration system

作　　者：肖莲珍[1] 池鹏辉 王晨露[1] 刘晓琴[1] 刘洁[1] 

机构地区：[1]武汉工程大学材料科学与工程学院,湖北武汉430073

出　　处：《混凝土》2013年第12期46-49,共4页Concrete

基　　金：湖北省教育厅科学技术研究计划重点项目(D20121501)

摘　　要：原始排放磷渣以0-40％替代水泥掺入到水泥净浆中，凝结时间、抗压强度结果显示了磷渣对水泥水化的延缓效果；借助化学收缩和电阻率监测其水化过程及定量地了研究磷渣对水泥水化机制的影响规律。与空白水泥浆相比，磷渣掺量越高，缓凝效果越显著，当磷渣掺量为40％时水泥浆体的初凝／终凝时间延长了4．43／3．64倍；同时磷渣掺人降低了浆体3、28d的抗压强度值，各磷渣掺量对3d强度降低幅度较大。化学收缩结果表明：对水泥的水化而言，在硬化阶段，磷渣起了一定的促进作用；对整个水化体系而言，磷渣起延缓体系的水化作用。磷渣延缓水泥水化主要由磷渣中含有的残余磷酸和部分替代水泥的稀释作用引起，其中水化早期磷酸的缓凝作用占主导。电阻率结果表明：在水化体系的硬化阶段，空白样品和掺磷渣样品水化体系的反应速率分别为3．588、3．543（Ω·m）／h；胶凝材料颗粒的平均反应速率分别为O．321、0．187h-1。The paste samples were prepared using original phosphoms-slag（PS ） by contents of 0-40% to replace cement.The setting time and compressive were measured of the pastes for studying retarding effect of phosphorus-slag, and the electrical resistivity and chemi- cal shrinkage measurements were used to investigate hydration mechanism of the blended system of cement and phosphorus-slag.The more phosphorus-slag content shows the significant retarding effect.With comparison of the plain paste, the paste with 40% of the phospho- Ms-slag postpones initial/final setting times by 4.43/3.64 times.The replacement of cement by phosphorus-slag leads to decrease in com- pressive strength, the largest decrease rates are 57% and 35% at 3 d and 28 d, respectively which shows a more significant effect of phos- phorus-slag on early strength than on late age due to phosphorus-slag pozzolanic activity.The results from chemical shrinkage show that the retarding effect of the phosphorus-slag on early hydration is mainly attributed to acidic impurities and secondly attributed to the replace- ment of cement.The addition of the PS shows an improvement effect on cement hydration and a dilution effect on the hydration system.The results from electrical resistivity are that the hydration rates are 3.588 and 3.543 （Ω.m）/h, the average reaction rates of cementitious parti- cles are 0.321 and 0.187 h-1 for the plain sample and the sample with 20% SP replacement, respectively.

关 键 词：磷渣 水化 缓凝 电阻率 化学收缩 

分 类 号：TU528.01[建筑科学—建筑技术科学]