Simulation and Prediction of Settlement of Old and New Foundations of Bridges in Cold Region Based on Temperature-Displacement Coupling

Predicting the rough settlement difference between old and new pile foundations in a certain period of time is conducive to the reliability evaluation of settlement control technology for widening Bridges. The temperature-displacement coupling model of pile-soil interaction was established using Abaqus large finite element software, and sensitivity analysis was carried out on the vertical deformation of old piles under different new pile diameter and pile length, the transverse deformation of old piles and additional bending moment. The settlement law of bridge pile foundation in cold region is revealed from the perspective of construction control from old pile pressure, construction environment temperature and construction sequence of new pile. New pile excavation will lead to “earth squeezing effect”, which will be weakened by concrete pouring, while old pile compaction can effectively reduce the “earth squeezing effect”; With the change of construction environment temperature, the influence of new pile construction on the internal force and deformation of old pile changes significantly. The study can provide methods and suggestions for the construction of bridge pile foundation in cold area.