Research On Comprehensive Maintenance Technology Of Ballastless Track Lifting And Rectifying Deviation For Operating High Speed Railway

At present,the development of Chinese railway is advancing by leaps and bounds,forming a large-scale railway network.Compared with the design and construction,the operation and maintenance of railway has become the focus and difficulty.Under the long-term effect of complex environment and vehicle load,there are many types of diseases.Among them,subgrade settlement and migration are common diseases at present,which affect the smoothness of the line and the safety and comfort of driving.Due to the limited capacity of fastener adjustment,the guarantee of line smoothness needs to rely on more effective control measures.Based on the actual situation of short skylight time and heavy maintenance task,combined with the characteristics and maintenance rules of ballastless track,this paper carries out the research on the treatment technology of settlement and offset disease of linear section in subgrade section of high-speed railway.This paper has done the following work:(1)In view of the existing ballastless track settlement deviation disease and the corresponding treatment technology are discussed.On the basis of summarizing different lifting correction technologies,the shortcomings of the existing treatment methods are compared and analyzed.In order to provide reference for the maintenance and repair of high-speed railway in China,the paper puts forward the basic methods suitable for the rapid treatment of high-speed railway subgrade settlement deviation disease during operation.(2)Based on the settlement disease of the two-block ballastless track subgrade section,the mechanical lifting scheme was designed,the principle and requirements of mechanical lifting were analyzed,and the safety calculation of the lifting structure was carried out.Through the establishment of ABAQUS finite element model,the influence rules of lifting distance,single lifting amount,fastener system and other factors on lifting effect were studied.(3)Based on the double-block ballastless track subgrade section migration disease design deviation correction scheme,analysis of the principle and method of deviation correction.Through ABAQUS finite element software,the model analysis of the deviation correction process of ballastless track is carried out.Analyze and compare the correction effect of single-point jacking and multi-point jacking.The rectifying length,disconnecting length and interlayer friction coefficient applicable to the proposed method are discussed.The performance of the track structure under different working conditions is compared and analyzed to evaluate the rectifying effect.(4)Relying on the lifting project of a section of ballastless track on Weijing Line and the deviation correction project of a section of ballastless track on An6 Line,the disease control construction process,construction content,construction method and monitoring scheme under the time limit of skylight are studied and designed.It also introduces the matters for attention in the construction of jacking rectifying deviation.The research results are as follows:(1)the larger the lifting distance is,the easier the track structure is to be damaged by bending;The stress value of track structure increases linearly with the amount of single lifting,so it is recommended to use multiple lifting and the amount of single lifting should not be too large;It is suggested to remove the fasteners before and after the lifted Track Bed Slab(track slab)area.(2)Too long or too short rectification length is not conducive to rectification operation,and it is suggested that the rectification length should be more than 30m;The dissociation length should be increased with the increase of the correction length.Increasing the dissociation length can effectively improve the correction amount;The larger the friction coefficient between layers is,the more unfavorable the rectification operation is.It is suggested to reduce the friction as much as possible.Through the design and modeling calculation of the reaction structure in the rectification operation,it is verified that the force and deformation of the reaction structure meet the requirements.(3)The specific construction steps of on-site settlement disease treatment are: determining the line lifting amount,unlocking the track plate,installing lifting equipment,lifting the track plate,grouting filling,removing lifting equipment and accessories,connecting the track plate,fine adjusting the track,and cleaning the construction site.The specific construction steps of on-site deviation rectification are as follows:determining the line deviation correction amount,planting reinforcement and anchoring,setting reaction pier,arranging measuring points,installing jacking deviation correction equipment,removing plate bottom constraint,jacking deviation correction,grouting,removing lifting deviation correction equipment,restoring the line,and cleaning up the construction site.The feasibility of the treatment scheme is verified by the field treatment results.In general,the jack lifting and deviation correction have good effect.The research results of this paper can provide some reference for understanding the principle and process of lifting rectification and improving the disease treatment of high-speed railway during operation.