| Given the occurrence of diseases such as cracking and arching,settlement and displacement of high-speed rail track slabs,subgrades,and tunnel bottoms,it is necessary to rectify the diseases of support lines and restore the line status without interrupting traffic.How to simplify the tedious support construction plan,how to reasonably solve the problem of the temporary speed limit in the line area,and how to check the status of the support equipment are the keys to ensuring the safety,driving efficiency and equipment stability of high-speed rail lines.Combined with the support requirements and characteristics of the line,this paper conducts an in-depth study and analysis of the support technology of the high-speed railway ballastless track line based on the steel cushion beam structure.The finite element analysis software is used for analysis,and the validity of the design is verified by the laboratory test results of steel cushion beams.To improve the speed limit in the support area,the dynamic simulation of the support device was carried out,and the traffic speed standard of the support device was proposed.According to the design of the support installation,the inspection and maintenance guide scheme is put forward.The main research results and conclusions of the paper are as follows:（1）The size of different types of ballastless track slabs and the size of D-type facilitation beams were systematically investigated,the span,beam height,and structural section form of support devices were compared,and a ballastless track that could be laid on high-speed railways was researched and proposed.Temporary support installations on lines.At the same time,in order to improve the applicability of the support device in different support areas,for a certain track slab or multiple track slabs of the ballastless track,it is proposed to solve the problem of a track slab,multiple continuous track slabs,and two track slabs.3 support overall schemes for disease.In order to simplify the process,combined with the boundary conditions of the singlepiece steel cushion beam design,the steel cushion beam,transition support,support,limit device,fastener and connecting plate of the support device are designed.（2）According to the design,finite element analysis software is used to simulate and analyze the strength,stiffness and stability of the steel cushion beam,the core forcebearing component of the support installation.The results of finite element analysis show that: under the action of CRH3 trainload,the vertical deflection,beam end angle and lateral deflection of the steel cushion beam all meet the requirements of the specification.And the strength and stability of the steel cushion beam obtained by the check meet the design specifications.According to the laboratory conditions,the loading test of ZK special load and CRH3 train load was carried out.The indoor test verified the maximum vertical deflection of the beam mid-span,beam end angle,maximum pressure,tensile stress.（3）To ensure that the train can safely pass through the temporary support area at a speed of not less than 80km/h,a speed standard considering the static geometric irregularity of the line is proposed.The vehicle-bridge coupling dynamic analysis is carried out,and the dynamic response of the steel cushion beam and the train during the erection of the steel cushion beam is analyzed.The rationality of setting the allowable deviation management value of the track static irregularity is verified by the preset track static irregularity deviation amplitude of 5mm and 9mm.（4）A set of manufacturing acceptance standards and installation guidelines are set up from the five aspects of steel cushion beam parts processing,assembly,basic dimensions of finished products,painting and installation.The hierarchical model of comprehensive acceptance of steel pad beams is established,the weight of acceptance indexes is determined,the treatment methods of different acceptance indexes are determined by a fuzzy comprehensive evaluation method,and an inspection and maintenance system.To keep abreast of the working status of each component in the temporary support line and ensure the safe and stable operation of the vehicle,a maintenance plan for the temporary support line based on the acceptance system is formulated during operation.（5）The dynamic performance test plan of the steel cushion beam on the ballast line is put forward,the purpose and principle of the test are clarified,and the test content,the specific indicators of the test and the test equipment are arranged.For the installation and construction of the device,the construction flow chart,specific construction steps,personnel,equipment and materials required for the construction are provided,which is conducive to formulating a special construction process.The temporary support renovation of high-speed rail belongs to the research category of high-speed rail overhaul technology,and it is a forward-looking plan for uninterrupted traffic.It should be a technology that needs to be reserved for high-speed rail line maintenance in my country.Because the speed limit of a large number of support technical solutions for ordinary-speed railways is 45km/h,there are few types of research on temporary support technology for high-speed railway operation characteristics.In this paper,the overall scheme of the temporary support device for ballastless tracks of high-speed railway lines is proposed.In order to adapt to higher traffic speeds,the structure design of each component is carried out.The mechanical performance and safety of the support device are verified through experimental tests.The speed standard guides the line status management during the support period;the inspection and maintenance guidelines for temporary support installations are proposed,which systematically manage the status of the steel cushion beams and reduce the impact of support maintenance on high-speed railways.Compared with the existing support device with a design speed of 45km/h,the on-site assembly is convenient,the disease rectification space is larger,the train operation efficiency is improved,and significant economic benefits are produced.58 figures,40 tables,and 54 references. |
