Study On Frost Damage Treatment Technology Of Existing Line Subgrade In Cold Region Of Western China

Railway subgrade disease is one of the main factors affecting the safety and comfort of train operation.The main manifestation is the sinking,extrusion deformation(frozen,melt and sink)and mud squeezing caused by insufficient strength of the bed.The main reasons are poor soil quality,insufficient compaction density and water.The paper is aimed at the phenomenon of roadbed freezing damage in the line under the jurisdiction of Wuwei Works Section of China Railway Lanzhou Bureau Group Co.,Ltd.from the beginning of November to the next year in May of the next year,and the cause of the damage caused by roadbed freezing damage and the corresponding treatment.Measures to solve the problems of frequent changes in the geometrical dimensions of the line caused by frost damage,maintenance and repair work and maintenance costs,and the deterioration of line quality endangering traffic safety.The section where the roadbed frost damage is more serious is mainly located in the Wuchang Works Section,which has the Jinchang-Shandan section of the Lanxin Passenger and Freight Line Railway.The average altitude of the section line is 2200 m,the temperature in winter is generally low,and the minimum rail temperature can reach-24°C.This section mainly fills the high embankment section with collapsible loess.Because the collapsible loess has strong water absorption,in the low temperature state in winter,the roadbed frost damage is prominent,resulting in large equipment geometrical changes,for daily lines.Maintenance and repair has brought great difficulties.To this end,a series of experimental studies have been carried out in conjunction with relevant research institutes.Based on the analysis of various roadbed freezing damage observation data,the main causes of the roadbed frost damage in the cold regions of the western region and the prevention and treatment measures are summarized.The work is as follows.Firstly,aiming at the specific phenomena of railway subgrade diseases in the cold regions of western China,the main causes of the diseases are analyzed,and the existing remediation methods of railway subgrade diseases are analyzed in detail,from the existing replacement packing,composite geomembrane sealing method,changing load stress distribution,and doing Choose a suitable treatment method suchas a good drainage system,and evaluate the rationality of disease remediation from the perspective of mechanical analysis.Secondly,this paper analyzes the roadbed diseases of the Lanxin Railway in the western cold area,studies the natural,landform and hydrological characteristics of the roadbed frozen damage section,and confirms that the main disease cause of the line is caused by the roadbed freezing damage according to the freeze damage measurement results.The main mechanism of action of freezing damage is analyzed from the aspects of nature,physics and chemistry.Finally,effective remediation measures were taken for the causes of freezing damage of railway subgrade diseases in the western cold area,and the general minor disease remediation,laying of composite geomembrane replacement and remediation methods,salt remediation measures,and grouting remediation measures were analyzed.The focus is on the effect analysis of the four sections of replacement and remediation measures,and the height and frequency of roadbed freezing damage are significantly reduced.The research on the paper is more important for scientifically and effectively rectifying the roadbed frost damage in the cold regions of the western region,reducing the disturbance of roadbed frost damage to the order of the existing train transportation organization,and ensuring the safe and smooth flow of railway transportation.