Experimental Study On Performance Of Stone Powder Mortar

With the gradual depletion of natural sand resources and mining restrictions,the existing supply of natural sand has been difficult to meet the production demand of cement,mortar,etc.In the process of stone processing,it is inevitable to produce some sawdust.The particle size less than 0.075mm is called stone powder.In the past,this part of waste powder has been piled up in the factory as waste,which is useless.It is a waste of resources and pollutes the environment.With more and more attention paid to the concept of environmental protection,the resource consumption of cement and the environmental pollution produced in the process of cement production have been paid more and more attention at home and abroad.Replacing a certain proportion of cement with stone powder,mixing with sand and water to make building mortar can not only effectively use waste stone powder,realize the full utilization of resources,but also reduce the consumption of cement and reduce the cost Environmental pollution has gradually become a new research topic at home and abroad.In this paper,granite powder is used to replace part of cement and mix with water and sand to prepare mixed mortar.The main research work and results are as follows:?1?Chemical composition and microstructure analysis of stone powder.The results show that the main components of stone powder are SiO₂ and Al₂O₃,and the particle shape is irregular,most of them are flat and have irregular edges;?2?Research on the influence of stone powder content on mortar performance.In order to study the influence of stone powder content on various properties of mortar,the stone powder content is 0%,5%,10%,15%,20%,25%and 30%respectively.The results show that:with the increase of stone powder content,the consistency of mortar first increases and then decreases,the water retention rate increases,the apparent density decreases,the setting time decreases,and the compressive strength and flexural strength first increases and then decreases.When the content of stone powder is 10%,the mechanical property of mortar is the best,the working performance also meets the requirements of the specification,and the comprehensive performance of mortar is the best;?3?Research on the influence of stone powder content on the microstructure of mortar.The results show that:the compactness of stone powder mortar is generally not as good as ordinary mortar,the surface of stone powder mortar is loose and has more pores;the surface of ordinary mortar is dense and has less pores.