Preparation Of Decorative Mortar From Waste Granite Powder And Its Properties

With the development of the stone industry,stone waste is increasing.Due to the different types of waste and complex components in each region,it makes the utilization of waste difficult.In order to respond to the national call for energy saving and environmental protection,and promote the green development of industry,the experiment takes the waste granite stone powder from Yantai,Shandong Province as the research object and applies it to the decorative mortar.The main research is to study the effect of the change of the doping amount of each component of decorative mortar on its working performance,mechanical performance,flooding performance,durability performance,microscopic morphology and other properties,in order to realize the resource utilization of waste stone powder while preparing decorative mortar with excellent performance,and to provide suggestions for the resource utilization of waste stone powder.The main research contents are as follows.(1)The effects of stone powder dosing,cellulose ether dosing,dispersible emulsion powder dosing,defoamer dosing and water repellent dosing on the working properties,mechanical properties and flooding properties of decorative mortar were analyzed by experiments.When the amount of stone powder is less than 40%,the mortar performance meets the specification and has good performance;after the amount of stone powder is more than 40%,the working performance of decorative mortar becomes poor and the phenomenon of water secretion is serious.Redispersible emulsion powder can improve the compatibility of decorative mortar and increase the tensile bond strength of decorative mortar.Cellulose ether has a strong water retention and thickening effect,and the consistency of decorative mortar decreases with the increase of its admixture.Water repellent can reduce the water absorption of decorative mortar.The mechanical strength of decorative mortar increases and then decreases with the increase of antifoaming agent,and the bond strength of decorative mortar decreases by 64.94% when the antifoaming agent is increased from 0.03% to0.04%,then the antifoaming agent should not be mixed too high.(2)The interactions among four factors of stone powder,dispersible emulsion powder,cellulose ether and defoamer were analyzed by orthogonal test,and the recommended ratio with better overall performance was obtained.The test results show that the effect of stone powder on the mechanical properties of decorative mortar is the greatest,and the mechanical properties of decorative mortar decreases with the increase of its dosing;the effect of redispersible emulsion powder on the working properties of decorative mortar is the greatest,and the compatibility of decorative mortar is improved with the increase of its dosing;the effect of cellulose ether on the consistency and water absorption of decorative mortar is the most obvious.Based on this optimized ratio,the aging cycle tensile bond strength test was conducted to verify that the aging cycle tensile bond strength of the decorative mortar met the requirements after the optimized ratio.(3)The performance of the decorative mortar was optimized by adjusting the grading of the stone powder,and the test results showed that the performance of the decorative mortar could be improved by designing the grading of the stone powder,thus increasing the utilization rate of the stone powder.(4)The analysis of the results of the mercury-pressure test shows that the porosity of the decorative mortar increases,the average pore size increases and the empty area decreases with the increase of the stone powder admixture.The results of scanning electron microscope test can be seen that stone powder will reduce the hydration rate of decorative mortar and make the hydration products of decorative mortar loose and porous.Redispersible latex powder does not form a membrane structure in the decorative mortar in the early stage,which has little effect on the performance of the decorative mortar,but in the later stage the powder forms a spatial reticular membrane structure with the hydration products interwoven distribution to enhance the mechanical strength of the mortar.