Study On The Influence Of Marble Powder On Physical And Mechanical Properties Of Cement-based Materials

Cement-based materials are widely used in construction,transportation,water conservancy and other projects.Mineral admixtures can improve the cement-based materials'performance and save the engineering costs.Guangxi is the largest white marble producing area in South China.It produces 800,000 tons of marble waste powder every year,which seriously pollutes the environment.To be a new type of green building material,marble waste powder can be used as mineral admixture,which has good environmental protection,technology and economic benefits.Because of the chemical composition,particle size and morphology of marble powder and marble waste powder are obviously different from those of traditional mineral admixtures,it is of great practical value and theoretical significance to study the influence of the above characteristics on the properties of cement-based materials and the mechanism of action.This paper mainly studies the physical and chemical properties of marble powder,such as particle structure and mineral composition,the influence of marble powder on cement hydration process and the evolution of the microstructure of marble powder cement hydration process,the influence of marble powder fineness and content on the physical and mechanical properties of cement,the working performance of marble powder concrete,such as collapse,bleeding rate,apparent density and density.Physical properties such as compactness,capillary pore coefficient,cubic compressive strength,splitting tensile strength,flexural strength,axial compressive strength,modulus of elasticity and other mechanical properties of marble powder cementThe following results have been achieved in this paper1.The fractal geometry model of particle volume distribution was established With the increase of fractal dimension,the particle size becomes smaller and the roundness becomes better.After the powder intermixing with each other,the larger the fractal dimension is,the tighter the accumulation will be2.The change of calcium hydroxide content in the hydration products of marble powder cement indicates that marble powder promotes the early hydration of cement,but is unfavorable to the middle and late hydration after 14 days.Artificial marble waste powder inhibits the hydration reaction of cement because it contains polyester resin3.The water requirement of marble powder cement is less than that of cement.With the increase of the content of marble industrial powder,the water consumption of marble powder cement is decreasing,so the marble industrial powder has water reducing effect on cement,and the finer the particles the more obvious of water reducing effect is.The setting time of marble powder cement is controlled by water consumption,and is also related to the fineness of marble powder.The strength of marble powder cement mortar mainly depends on the and cement leads to "volume overflow" of concrete,which makes some marble powder have skeleton supporting effect in concrete system.6.Less than 5%of 600 mesh marble powder and cutting marble waste powder can be used to produce cement,less than 10%of cutting marble waste powder can be used to replace cement inordinary concrete,and less than 25%of cutting marble waste powder and artificial marble waste powder can be used in ordinary concrete.