Research On Stress Releasing And Maintenance Technique Of Seamless Turnout

Seamless rail is an important symbol of technical progress of track structure and the best choice for rail structure of high-speed,heavy-duty and urban rail transit.Practice has proved that seamless line is widely used all over the world because it cancels a large number of rail joint rail joints,reduces train impact and vibration to rail joint,reduces joint diseases greatly,and reduces rail maintenance greatly.Therefore,seamless line is advantageous to smooth running and prolongs service life of equipment.As one of the key technologies of cross-section seamless track,seamless turnout is affected not only by the basic temperature force,but also by the temperature force transmitted by the frog and the straight and curved guide rails.Longitudinal temperature force transfer of seamless rail redistributes in the turnout range and forms a peak temperature force at the end of the switch.Therefore,the design theory and force analysis of seamless turnout have been paid attention to since 1993 when it was studied in China,and it is also one of the difficult problems in developed countries of world railway.At present,the main passenger and freight common lines within the jurisdiction of Jinan Bureau,such as Beijing-Shanghai,Jiaoji and Yanshi,have basically completed the laying of cross-section seamless lines.For the sake of saving investment,the original92-type,speed-up turnout and even 75-type turnout still remain in operation in each line.At present,the types of seamless Turnouts on the line are widely used and numerous.Due to the difference of management level of seamless turnouts in each station(equipment management unit),the theoretical research level on stress mechanism and stress distribution of seamless turnouts is different.There are many differences in lockin rail temperature setting,stress release,disease prevention and treatment,maintenance and maintenance management during daily construction and maintenance.Lack of effective uniform standards.This study takes seamless turnouts in the jurisdiction of Jinan Bureau as the research object,through the investigation of the state of each station,to understand the disease information of seamless turnouts in different stations and different map numbers.Through investigation,the seamless turnout diseases are sorted out,summarized and classified,and the types,causes,possible consequences and remedial measures of the diseases are analyzed.Then,by studying the force transmission mechanism of seamless turnouts,the force law of seamless turnouts is mastered,the hidden dangers of the diseases are eliminated as far as possible at the source,and the management measures for the turnouts are strengthened.Through the research on stress relief construction technology and maintenance and repair technology,the locking rail temperature of the turnout is adjusted in real time and reasonably during the operation and routine maintenance and repair of the turnout,so as to eliminate the negative impact on the turnout caused by stress concentration or abnormality.Through the research on longitudinal force and stress release technology of seamless turnout,it provides technical guidance for seamless turnout laying,stress release and maintenance of seamless turnout in Jinan Bureau,which has great theoretical and practical significance.