Research Effect Of Plasticizer On The Performance Of Alkali-Activated Slag Cement

Nowadays,the sustainable development of social and economic is significantlyinfluenced by the level of application technology of cement and concrete as the mostwidely application and the most largely quantity used in project structure materials,somore and more attention has been paid to how to reduce the negative effects on resource,energy and environment due to cement industry. On the contrary, the exploitation andutilization of alkali-activated slag cement with a simple production process, low energyconsumption, low investment, low greenhouse gas emission and effective use ofindustrial by-products is according with the strategy of sustainable development onsocial economy.It is a mostly problem to embarrass application of alkali-activated slag cement andconcrete which has many excellent performance, such as high strength, rapidhardening,low heat of hydration, good durability and so on that is big viscosity and badworkability of the new mixture with conventionality water-cement ratio. Adulteratingplasticizer is an important techno-means to solve the problem. Up to now, no systematicstudy has been done on effect mechanism of plasticizer on alkali-activated slag cementand concrete.In order to solve this problem, the performance of plasticizer to the the surfacechemistry, hydration heat release behavior and paste of alkali-activated slag cement arestudied systematically in the different conditions, such as the dosage and the type ofplasticizer, alkali-activator and retarder and so on. The research results can beconcluded as following:1) The adsorption capacity of plasticizer in different cementitious materials is bystrong to the weak as follows: Portland> slag> AASC activated with NaOH> AASCactivated with water glass; The adsorption capacity of different plasticizers incementitious material is by big to smal as follows: naphthalene> calciumlignosulphonate> aminosulphonate; Joining retarder into AASC is helpful to improve theadsorption of the plasticizer on the surface of slag particles.2) ζ potential of AASC particles in aqueous solution is negative, besides,theincreasing amount of bsolute value of ζpotential of different cementitious materialsparticles with plasticizer is by large to small as follows: slag> AASC activated withNaOH> AASC activated with water glass; The increasing amount of bsolute value ofζpotential of different plasticizers in AASC is by big to smal as follows: naphthalene> calcium lignosulphonate> aminosulphonate; Joining retarder into AASC is helpful toimprove the increasing amount of bsolute value on the surface of slag particles.3) The different plasticizers to hydration heat behavior of AASC is different asfollow: Joining retarder into AASC, the rate of hydration heat evolution and hydrationheat of AASC with calcium lignosulphonate and aminosulphonate were lower,byconctrast, naphthalene improves the hydration degree and heat of AASC.4) The Findings Indicates that flowability of AASC has little related with theplasticizer, however, the workability of cement mix was improved obviously whileretarder was joined into AASC with plasticizer.