Reseach On The Mechanical Lifting Technology And Materials Of High Speed Railway Unballasted Track Settlement Disease

With the gradual formation of China's high-speed railway network and the rapid increase of high speed railway operation mileage,the diseases of high speed railway unballasted track line is gradually emerging.Settlement disease is one of the typical form of the diseases.Longterm train loads and complex natural environment lead to the local part subgrade settlement,which endanger the safety,smooth and comfortable of the high speed railway.The low maintenance time,high requirements construction's quality and small structural damage are required on the repairing projects of high speed railway subgrade settlement.In this paper,a complete set of construction technology and equipment are put forward,and the cement-based materials of high speed railway unballasted track settlement servicing are studied in depth with the research methods of data research,indoor model test and orthogonal experiment of material formula.The main research works are as follows:1.In this paper,the regulation scheme of unballasted track settlement disease with threaded rod lifting is designed by researching and drawing lessons from the existing technology on the regulation of settlement disease.The threaded rods and other supporting equipment are designed and made to realizing the scheme.Through some indoor model tests,the relationship between the penetration depth of the threaded rod and the bearing capacity,and the strength of the adhesive bonding are measured.The feasibility of the screw lifting was verified,and the lifting equipment was improved and optimized.2.Through material formulation tests carried out by orthogonal test method,the influence law of the cementing materials,polymer,water reducing agent,retarder,early strength agent and other components on the mechanical performance and construction characteristic of cement based materials' are studied.The applicability of different materials to the high speed railway settlement disease servicing is researched.The better mixing amounts of each materials are put forward.3.The material research shows that adding the right amount of polymer emulsion can improve the fluidity of cement mortar,reduce the compressive strength,improve the folding strength,increase the pressure ratio,and improve the road performance of the material.Adding the right amount of sodium gluconate and lithium carbonate in sulpho-aluminate cement at the same time can keep the liquid,form a high early strength,and the strength of 28 day is no decreasing.4.The formula of polymer cement mortar was obtained to meet the rapid construction requirements of high speed railway settlement servicing.The material is composed of sulphoaluminate cement,fine sand,water reducing agent,polymer emulsion,retarder and early strength agent.It has good construction performance and mechanical properties.