| With the rapid development of underground space construction in China,grouting materials have been widely used.Pure water slurry has the advantages of low price,wide source of raw materials and high stone strength,but it also has the disadvantages of high water release rate,poor stability and low stone rate,which will reduce the quality of grouting project and affect the construction period.Therefore,admixture is added to the cement slurry to improve the slurry performance.ultra-fine slag powder metakaolin cement grouting material is selected as the test object,and the influence of superfine slag powder and metakaolin on the performance of cement slurry is studied.The fluidity,water evolution rate and viscosity of cement grouting material mixed with different amounts of superfine slag powder and metakaolin are carried out,and the mechanical properties of consolidated body at different curing ages are tested.The effect of magnetized water with different magnetization parameters on the performance of ultra-fine slag metakaolin cement grouting material was studied by adopting the optimal amount of admixture.The main research contents are as follows:Firstly,the composition,structure and performance of each component of the ultra-fine slag powder metakaolin cement grouting fluid are analyzed,so as to make full use of the advantages of each component material of the slurry.The fluidity,viscosity and water evolution rate of cement-based grouting materials with different contents of ultra-fine slag powder(15%,20%,25%,30%)and metakaolin(0%,3%,5%,7%,9%)were tested,as well as the flexural strength and compressive strength at different ages.The test results show that:when the content of metakaolin remains unchanged,with the increase of superfine slag powder,the viscosity of slurry and compressive strength of consolidated body gradually increase,while the fluidity of slurry and flexural strength of consolidated body gradually decrease.When the content of superfine slag powder remains unchanged,the fluidity of slurry decreases and the viscosity increases with the increase of metakaolin content.When the content of metakaolin is in the range of 5%～7%,the compressive strength of consolidated body is better.The effect of adding superfine slag powder to pure water slurry is small,but the effect of metakaolin is obvious.The viscosity and fluidity can be effectively controlled by adding appropriate amount of metakaolin and superfine slag powder,and the strength of consolidated body can be improved.Secondly,using magnetized water instead of ordinary tap water to stir the superfine slag metakaolin cement grouting material,the magnetizer with 285mT magnetic field intensity was selected to study the effect of magnetized water(6L/min,9L/min,12L/min,15L/min)flowing through the magnetizer on the performance of cement grouting materials mixed with ultra-fine slag powder(25%,30%)and metakaolin(5%,7%)Magnetized water is beneficial to improve the fluidity and consolidation strength of cement-based grouting materials with different contents.Magnetized water can significantly reduce the water separation rate of the slurry.Through the comparison of the test data of each group,it is concluded that the performance of the cement grouting fluid mixed with 25%superfine slag powder and 5%metakaolin mixed with magnetized water with water flow of 6L/min is better.Finally,the performance of cement grouting material mixed with superfine slag powder(25%)and metakaolin(5%)under different magnetic field strength(285mT,330mT,810mT)and different magnetized water flow rate was studied.The test results show that the magnetized water under different magnetic field strength is conducive to the improvement of fluidity,flexural strength and compressive strength of cement-based grouting fluid and the decrease of water separation rate.The strength of slurry consolidation body with 285mT magnetic field strength is significantly higher than that of 330mT and 810mT,and the fluidity of slurry with different magnetic field strength is 810mT,285mTand 330mT.By comparing the data of each group,it is concluded that the performance of cement-based composite slurry prepared by magnetic water with 285mT magnetic field strength and 6L/min water flow is better.Figure 28 table 24 references 95... |
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