Preparation And Performance Study On The Alkali Activated Multicomponent Cementitious Material

Alkali activated multicomponent cementitious material is a new kind of cementitious material and made of alkali as activator,then slag,limestone powder,and glass powder as cementitious material.With excellent mechanical performance and resistance to corrosion,it is green and environmental.This thesis uses RSM in Design-Expert to optimize the mix proportion of each component of alkali activated multicomponent cementitious material.The microanalysis and resistance to corrosion test are also studied and the following conclusions are drawn:(1)The influence of content of water glass,limestone powder and glass powder to 3d,7d,28 d flexural and compressive strength of alkali activated slag mortar is studied.The results show that the strength of mortar increases when the content of water glass is from 4% and comes to maximum when the content of water glass is 8%.The strength of mortar increases most obviously when the content of limestone powder is 15%,while it increases most obviously when the content of glass powder is 10%.(2)Mechanical property is response value.RSM is used to optimize the content of water glass and limestone powder and glass powder in alkali activated cementitial material.The optimization results show the content of water glass,limestone powder and glass powder is 7.76%,14.77%,9.27% in alkali activated slag-limestone powder-glass powder cementitial material.The vertication test results show the error between predicted value and measured value is quite small.(3)XRD test results show the main hydration products of alkali activated slag cement are C-S-H,CaO·Al2O3·7SiO2·2H2O,Ca3Si3O8(OH)2,Ca5Si6O16(OH)2.There is a little Ca5Si2O7(CO3)2 in alkali activated slag-limestone cementitious material when the content of limestone powder is 15% in 28 d age.There is no new product in alkali activated slag-glass powder cementitious material when the content of glass powder is10%.TG-DTA test results show hydration product CSH of alkali activated multicomponent cementitious material loses water at around 100-200?.Then CaO·Al2O3·7SiO2·2H2O,Ca3Si3O8(OH)2 and other products lose crystal water at around 700?.SEM test results show the hydration of alkali activated cementitious material reacts a lot and limestone powder is made as addition material in early days.The structure of alkali activated mortar becomes denser and hydration products increase more with the increment of age time.(4)Compared to Portland cement,the resistance to Na2SO4,MgSO4,CH3 COOH corrosion tests conclude that alkali activated slag cementitial material,alkali activated slag-15%limestone powder cementitial material,alkali activated slag-10%glass powder cementitial material,alkali avtivated slag-15%limestone-10%glass powder cementitial material show more excellent resistance to corrosion.But the resistance to corrosion reduces when the content of limestone powder and glass powder is excessive.