Study On The Properties Of Filling Material Reinforcement Of Soft Coal Roadway

Coal beds in a coal mine in Shaanxi are soft,the roadway is soft coal roadway,resource recovery rate is low,roadway maintenance engineering quantity is big,the backfill support is the key technology to solve the problem of soft coal roadway.At present,the commonly used roadside filling materials in China and abroad are paste filling materials and high water filling materials,The raw materials of high water filling materials are few,the cost is high and the production process is cumbersome,On the contrary,paste filling materials can not only the source of raw materials widely,low price,the production process is simple,but also it can meet the technology and strength requirements of roadside filling support,So it is very important to study the properties of the paste filling material in the side of the mine.In order to find out the filling material which can meet the technology and strength requirements of roadside filling support,In this paper,the chemical composition of raw materials for filling materials ? Strength characteristics of three kinds of filling materials?experimental research on the characteristics of filling body is studied and analyzed.Analysis of chemical composition of raw material for filling materials: The laboratory tests of coal gangue,fly ash,coal powder,loess and other raw materials were carried out,the physical and chemical properties of the raw materials and the feasibility of the filling materials were obtained.Study on strength characteristics of reinforce filling materials: Three types of reinforcement filling materials were prepared by using the raw materials,uniaxial compression tests were made on specimens with different ratios of each reinforcement,the influences of fly ash / cement ratio,sand ratio and water cement ratio on the compressive strength of the specimen were analyzed and the linear regression analysis was carried out,get the strength prediction formula and meetthe requirement of the side filling process and strength,The best proportion of filling body suitable for Lane,the shear strength indexes of the filling body were studied,Experimental study on the characteristics of reinforcement filling body: According to the above research results,indoor performance analysis test of the best proportion filling body sample was carried out,the relationship between axial compressive stress and strain of III type filling specimens with three kinds of ratios was studied,the strain and elastic modulus of the ultimate strength are obtained,the relationship between elastic modulus and compressive strength is analyzed;The test of acid and alkali resistance of the filling body was carried out,the changes of compressive strength of filling body in water solution,acid solution,alkali solution and sodium sulfate solution were analyzed,and obtained the prediction formula of the coefficient of hydrolysis and the change of the strength with time in each solution;Thermal stability test of filling body sample was carried out,The influence of temperature on the strength of the specimen was obtained and the prediction formula of the strength of the filling body at different temperature with time was obtained by fitting analysis.