Study On The Differential Settlement Of The Mountain Slope Subgrade In Passenger Dedicated Line

Based on Shanghai-Kunming passenger line roadbed fill slopes engineer, This paper focused on the mountains differential settlement of sub-grade fill slopes, researched the relationship between supporting structure displacement and settlement of sub-grade, using finite difference software modelled differential settlement of sub-grade fill slopes. Main works and research results are as follows:1. Based on fill slopes embankment and retaining structures treated fill slope embankment, embankment settlement observation, force and displacement monitoring of retaining structures experiments was carried out. Experiment proved the relationship between lateral displacement of retaining structures and the differential settlement after filling, maximum differential settlement of sub-grade surface was0.72times of lateral displacement of retaining structures, the relationship between the size of the horizontal displacement of retaining structures and soil pressure of back wall was a positive correlation,the differences of horizontal displacement between Cantilever end and Depth end of retaining structures was caused primarily by the bending moment generated under soil pressure. In order to control the uneven settlement of Sub-grade cross section, measures can be taken to limit the lateral displacement of retaining structures, Improve the stiffness of retaining structures.2. Using Creep model, field test section was modeled by limited differential analog, the relationship between settlement and time under the creep model was obtained, the comparsion between the finite difference model results and field test results verified the finite difference simulation software reliability.3. Based on the FLAC3D finite difference software, the influence of embankment height, fill slope form, original foundation slope, original foundation soil and backfill modulus, retaining structures depth and position of retaining structures on the differential settlement were obtained, influence of these factors on the uneven settlement of fill slopes embankment in passenger dedicated line are also studied in the paper. By reducing the original Foundation slope, increasing retaining the depth, improving fill soil and foundation soil modulus, making retaining structures as close as possible to the midline Under the condition of meeting the roadbed roadbed width requirements, it is effective to control the differential settlement of sub-grade cross section.Through field tests and numerical simulation, the relationship between retaining structures displacement and uneven settlement was obtained, verified the reliability of the finite difference software simulation, analyzed the influence of different factors on the uneven settlement, which can guide the design and construction and settlement control of the future roadbed slope...