Study On Hydrating And Hardening Mechanisms Of High-Water Rapid-setting Material

With the rapid development of economy and the increase of the construction,the building material is required with excellent performance in the construction which is in the sensitive environment with specific function to ensure the safety of the building. High-water rapid-setting material is a new type of high water-cement ratio cement-based material,which has the advantages of rapid setting,early strength,good liquidity and environment friendly,and it has been widely used in soft soil foundation treatment, emergency project and reinforcement of rock.The hydration and hardening of high-water rapid-setting material is researched from two aspects of macroscopic and microscopic,and the main contents and conclusions are as follows:Effect of water-cement ratio, gypsum and lime dosage, curing conditions, curing temperature and test temperature on compressive strength of high-water rapid-setting material is analyzed by test, and the curves of compressive strength of high-water rapid-setting material under different variations is obtained.Then the optimal quantity of lime gypsum ratio and the best curing conditions is presented,which can provide reference for the design,the preparation and the application of high-water rapid-setting material.Taking the research method of the hydrating and hardening mechanisms of silicate cement,the hydration heat and chemically combined water content is tested under different water-cement ratios and different dosages,then the the hydration process and degree of high-water rapid-setting material is expressed from the angle of dynamic and static.Combining the microscopic detection methods of XRD,SEM and so on with the study on the compressive strength and the hydration process,the hydration products and the micro morphology of high-water rapid-setting material in each curing period under different water-cement ratios and different dosages is comparative analyzed,based on that,the hydration and hardening of high-water rapid-setting material is presented.The hydration of high-water rapid-setting material is the reaction process of sulphoaluminate cement, gypsum and lime,which can provide a strong basis for the standard research of high-water rapid-setting material.The unitary regression model of compressive strength of high-water rapid-setting material after curing 28 days with the water-cement ratio is presented using the MATLAB software to fit the compressive strength.The binary regression model of compressive strength of high-water rapid-setting material after curing 28 days with the water-cement ratio and the gypsum-lime ratio is presented using the principle of surface regression.The application conditions of two regression models is put forward through the comparative analysis,whichcan provide a powerful reference for the prediction of compressive strength of high-water rapid-setting material after curing 28 days.