Study On Preparation And Performance Of Geopolymers

Preparation of different geopolymers,and the analysis of macro-performance and microstructure were studied.The raw materials are mostly industrial waste which have much variety and different characteristics.Blast furnace slag,the slag from smelting zinc(hereinafter referred to as zinc slag),low calcium fly ash and high calcium fly ash as raw materials.In order to understand the structure properties of raw materials,the relationship of materials activities and composition,micrographs and structure were studied by XRD,SEM and FTIR analysis methods.Finding out basic laws from experimental exploration,and evidence from macro performance.Laying foundations of forecasting the feasibility of the unknown active materials.Different raw material reactors are slightly different,but the existing mixture ratio calculation method is single and can not fully stimulate their activity.The method of designing mix proportion for high-activity based on the theory of PSS long chain proposed by Davidovits.For raw materials with poor activity,changing the modulus and amount of sodium silicate to depolymerize the long chain.Providing ideas for stimulating new materials.Because of the great differences properties of raw materials and the reaction process.The characteristics of raw materials during alkali activation are revealed.The differences and relations were summarized by SEM and FTIR analysis during reaction process.The components in activator influence on raw materials and the basic of geopolymers activated mechanism were comprehensively understand.Water is used as the medium during the process of geopolymer reaction.However,the effect of the amount of water consumption on the reaction and strength of geopolymer is not yet clear.The effect of water on the compressive strength is studied by changing the ratio of water to solid,and the role of water is discussed in depth by means of microscopic analysis.In addition,geopolymer reaction has a great temperature sensitivity.The effect of high temperature steam curing on the reaction process was discussed.The development trend of strength with steam curing were compared with room temperature curing and the reasons by microanalysis were explained.Bringing out the essence of endothermic and exothermic process in geopolymer reaction.