Development And Performance Study Of All-solid Waste Coal Gangue Permeable Brick

Coal mining produces a large amount of coal gangue,most of which is disposed by landfill or open-air stacking,causing environmental pollution.Therefore,Effective use of coal gangue,in order to alleviate the environmental pollution of coal gangue,the thing is impatient.The proposal of sponge city reduces the flood discharge pressure of the city.The pores inside the permeable brick make drainage easier,supplement groundwater resources and improve our living environment.The subject of the main research and development of permeable brick,Handan area of coal gangue as aggregate,solid waste-based cementitious materials as cementitious materials.The quality method is used to calculate the mix ratio,and the orthogonal test is used to analyze the importance and significance of each factor on the influence of permeable bricks.The trend of permeable bricks is studied when each factor changes.The cross-sectional area and pore area of the split failure section image are calculated and analyzed by digital image processing software.In this experiment,the process of preparing permeable bricks is summarized,and the mixing process and forming method are explored.Two groups of permeable bricks are selected from the orthogonal test for frost resistance research.The specific experimental research situation is as follows :(1)The development process of permeable brick was studied.The stirring process of this test was determined by analyzing and comparing the traditional stirring method and fractional feeding method.Through the comparative analysis of vibration molding and pressure molding,it is determined that the molding method of this test is vibration20 s plus static pressure 1.5MPa and pressure stabilization 30 s.(2)Orthogonal test design was carried out.Bone-cement ratio,water-cement ratio and ratio of coarse and fine aggregate were selected as the influencing factors of this test.Three levels were selected for each factor,and nine groups of tests were designed to test the splitting tensile strength and permeability coefficient of each group of solid waste coal gangue permeable bricks.(3)The factors influencing the performance of permeable brick were analyzed.Through the range analysis,it can be seen that the bone-cement ratio,water-cement ratio,coarse and fine aggregate ratio have an important influence on the splitting tensile strength and permeability coefficient of permeable bricks.The trend of splitting tensile strength and permeability coefficient changing with the level of each factor is explored.Through variance analysis,it can be seen that the influence of various factors on the splitting tensile strength and permeability coefficient of permeable bricks is significant.The prediction formulas of splitting tensile strength and permeability coefficient are obtained by fitting and analyzing the test data with JMP software.Based on digital image processing technology,Image J software is used to calculate the cross-sectional area and pore area of the split failure section image,and the influence of aggregate distribution and internal pores of permeable brick on splitting tensile strength and permeability coefficient is analyzed from the microscopic level.(4)The frost resistance of permeable brick was studied.Two groups of mix proportions with high strength and good water permeability were selected from the designed orthogonal test to study the frost resistance of the two groups of all-solid waste coal gangue permeable bricks.The results show that the frost resistance meets the requirements of the specification.Analyze the influencing factors of freeze-thaw damage.