Research On Settlement Of Joint Section Of Rebuilding Of Existing Railway

In the rebuilding of existing electric-railway the old and new lines will cross in some sections. It brings the problem of the uneven settlement between the new and old embankment, this is not only an increase of maintenance costs, but also a threat to the safe operation. At present, the research on the old and new embankment is more and more improved, but most of the issue is about widening the existing expressways. Railway embankment is rarely involved, there is no standard for the design and construction, the measures of treatment are mostly based on engineering experience, which often results in inappropriate treatment.The zhe-Gan line electrification project is the research background. This paper takes DK342 +480 from Yushan to Huyan and DK333 +120- DK333 +226 from Jujie to Huyan as two typical cross-sections. Considering two different ways of Combination, the planar and three-dimensional model is used respectively. Its theoretical hypotheses are Biot consolidation theory and Mohr-coulomb hyperbolic soil model.In the planar model, the influences on embankment and groundwork in the joint owing to widening are analyzed, including uneven settlement, horizontal displacement, pore pressure. In order to reduce uneven settlement in the joint, three treatment techniques including excavated steps, embankment reinforcement, light embankment, are compared in mechanism and applicable condition.In the three-dimensional model, the settlement rules on embankment and groundwork in vertical direction and cross-sectional direction in the joint are analyzed, considering the influences of the Different angles of the joint, the influence scope of uneven settlement is found.