Researching On Stable Performance Of Ballastless Track Embankment Structure In Beijing-tianjin Passenger Transport Line

Ballastless track is used in high-speed railway in China. Compared with ballasted track, the ballastless track is stricter to the roadbed subsidence deformation. Deformation control has become the most major characteristic of high-speed railway embankment. Our country's high-speed railway construction has just started. Beijing-Tianjin passenger transport line is China's first high-speed railway, which entirely used ballastless track and has operated. So the design parameters of the track, the control measures of embankment settlement and its effects have strong reference function to our country's large-scale construction passenger transport line. For this reason, this article based on the test section of Beijing-Tianjin passenger transport line has done the following research works:(1) Based on the actual s-t (subsidence quantity-time) data of Beijing-Tianjin passenger transport line, different sections were forecast for the settlement adopted the second curve-fitting method and the gray verhulst model. The results showed that the method has high accuracy, ease to use, good reliability characteristic. This research promote the railway informationization construction to our country and has high reference value.(2) In consideration of influence from the train and the track, the traditional theory of numerical simulation of the train load was promoted to the field of high-speed EMU, which has been simulated and imposed by ANSYS.(3) The three-dimensional entity finite element model of roadbed structure is established in consideration of interaction of pile and soil, elastic support of fastener, constitutive relationship of subgrade soil. The roadbed various structures's subsidence distortion characteristic and stress change rule under the dead weight load and train load is analyzed through uses this finite element model. The design parameters of roadbed in Beijing-Tianjin passenger transport line is evaluated.(4) Using the vehicles-track-embankment finite element model analysis the steady-state settlement and dynamic response of roadbed When stiffness of roadbed, elastic modulus of CFG piles, pile spacing and train speed changes, and further proposed the corresponding suggestion of design parameters.The research has important guiding sense and reference value on perfecting the design theory of high-speed railway ballastless track roadbed and later large-scale passenger transport construction...