The Study On Forming Reasons Of Track Plate Crack And Maintenance Technology Of Zhengzhou-xi’an High-speed Railway

Zhengzhou-Xi’an high-speed railway is the first railway whose design speed isover350km high-speed in China’s central and western regions. The whole railway lineof Zheng-Xi high-speed takes the double-block ballastless track as the rail base plate.After the railway line was formally opened, the staff found a lot of cracks in thejunction between the track plate and sleeper. The width and spacing of parts crack hasoutpaced design code. The appeared cracks will impact the service life of track plate.What’s more, the cracks under the action of the long-term intermittent dynamic load ofhigh-speed train trend to further expansion. So, it is necessary to study the formingreasons of track plate crack and maintenance technology, in order to provide the basisfor the formulation treatment program of track plate protection.This article finished the site cracks research. The research results show that thesurface cracks of track plate ware mainly concentrated in the junction between thetrack plate and sleeper. In the research, the widest cracks are up to1.15mm, and itsdepth is43.23mm, and over54%of the crack width has exceeded the crack widthlimits (0.20mm) of concrete specification. And finished the field measurement of thetrack plate’s strain response with the railway opening. The field vibration measuredresults show that the maximum strain response located in the four corners of thesleeper surface is up to67.0×10E-6. The calculated angle, which substantially perpendicular to the direction of cracks in the research.Next, it established finite element modeling of track plate, then analysis themodeling. The results show that strain response generated by the orbital plate under theexcitation of the train load has a decreasing trend located along the top facing of trackplate to the underside. The maximum strain caused by stress concentration due tomutations in its upper surface is up to71.8×10E-6. Combined with the measured dataand finite element analysis results, it show that the strain response of the track plateincented by train load is less than the concrete ultimate tensile strain value of102.6×10E-6considering the influence of reinforced. Therefore，It can be judged that theorbital plate cracks are non-load crack basis. The specific rehabilitation program iswhat can take the surface treatment method and grouting repair to the formed cracksselecting the epoxy resin and the curing agent as the crack repair materials.