Study On Mechanical Properties And Sulfate Erosion Properties Of Waste Glass Powder Cement Mortar

Because the glass itself is difficult to decompose and is buried underground,it not only affects the development of the soil,but also pollutes the natural environment.Recycling and reuse of glass can reduce pollution and save resources.Nowadays concrete is a widely used building material,and the resources are not renewable.The waste glass is made of waste glass concrete instead of fine aggregate as the best way to treat waste glass.The glass was ground to a certain fineness of the particle size,which had a high pozzolanic activity and could increase the strength of the cement mortar.Therefore,in this paper,the substitution standard sand of waste glass powder was added to cement mortar to study the feasibility of waste glass powder as fine aggregate.The main research contents and conclusions were as follows:(1)In this paper,five different sizes of waste glass powder were obtained by breaking,grinding and sifting the waste glass,and the effect of volume addition,particle size and maintenance age on the mechanical properties of cement grit was studied.The test results showed that the addition of glass powder of 200 mesh,500 mesh and 2000 mesh increased the mechanical properties of cement mortar;the addition of 100 pieces of waste glass powder could improve the mechanical properties of cement mortar and decrease the strength in the later period;and the later strength development of 20 mesh glass powder was inhibited,and the strength was always lower than the reference group.When the content of waste glass powder didn't exceed 20%,the flexural strength and compressive strength of the mortar were increased by 1.5%~33.3% and 0.2%~28.9% respectively.(2)In this paper,7 samples of waste glass powder cement mortar were selected for scanning electron microscope analysis.The test results showed that with the decrease of the particle size of the mixed glass powder,there were many flocculant gels attached to the surface of the cement clay matrix,which were well connected into a whole,the holes and pores were obviously reduced,and the microstructure were compacted.The glass powder mixed with a certain particle size and amount could effectively improve the compactness of cement sand matrix and increase the strength of cement sand in the later period.(3)In this paper,the influence of particle size and volume of waste glass powder on the performance of cement mortar against sulphate erosion was studied.The test results showed that the sulfate resistance of waste glass powder cement mortar increased first and then decreased.Within immersion time of sodium sulfate solution with a mass fraction of 5%,the waste glass powder cement mortar specimens couldn't be damaged by erosion,but the sulfur resistance was in a downward trend as a whole.