Study On The Application Of Cement Stabilized Waste Rock-Iron Tailings In Road Subgrade

With the rapid development of China’s steel industry,the demand for steel is increasing year by year.In steel industry,iron ore stripping waste and iron tailings become the main sources of industrial solid waste.Waste rock and iron tailings have many advantages,such as large output,large land occupation,environmental pollution,huge reserves and low utilization rate in China.Benxi is the main producing area of iron ore in Liaoning Province,with large reserves of iron tailings and waste rock.It is of great significance to study the roadworthiness of waste rock and iron tailings.Taking the stripping waste rock and iron tailings of Waitoushan Iron Mine in Benxi as the research object,this paper makes a systematic experimental study on the road performance of cement stabilized waste rock iron tailings road base,so as to realize the application of waste rock and iron tailings in road base.The main contents of this paper are as follows:(1)Experimental study on basic properties of Benxi waste rock and iron tailings.The physical and chemical properties of waste rock and iron tailings were studied,and it was determined that Benxi waste rock and iron tailings can meet the requirements of road performance.(2)Research on Gradation Design of cement stabilized waste rock iron tailings base material.According to the grading design theory,it is divided into two types: skeleton dense type and suspension dense type.The grading design and vibration compaction test are carried out respectively to determine the maximum dry density and optimal water content of each group of mix proportion specimens.The maximum dry density of skeleton dense type is higher than that of suspension dense type.(3)Laboratory test of cement stabilized waste rock iron tailings base material.The influence of cement,waste rock and iron tailings on 7-day unconfined compressive strength test,compressive resilient modulus test,splitting strength test,dry shrinkage test and frost resistance test of cement stabilized waste rock iron tailings was discussed.It is found that the base material has good mechanical properties when the content of iron tailings is 25%,the content of waste rock is 75%,and the content of cement is 5%.(4)The research results of this subject are applied to the engineering practice,and the cement stabilized waste rock iron tailings base material is laid in a secondary subgrade project in Benxi.The performance of the material in the subgrade application is tested,and the results meet the requirements of the specification.At the same time,the construction cost is greatly reduced due to local materials.Practice has proved that the research results have good application value.