Influence Of Deep Pit Excavation Of Heifei Subway On The Surface Of Adjacent Motorway

This article relies on a deep pit excavation of the Hefei subway project, analyzes the disturbance of the deep pit excavation on adjacent motorway. During the analysis, a three-dimensional finite element model considering the motorway as well as the deep pit excavation process is established. The maximum subsidence of the adjacent motorway and the distribution of the subsidence in different steps are emphatically studied.Some meaningful conclusions are obtained in the study:(1) Monitoring data showed that the displacement of retaining structure changes and the changes of the road and numerical simulation of though on the numerical size is not very close,but the change trend is very close.(2) After the excavation to the basement the maximum settlement of road surface is 7.77 mm, from the most distant of the foundation pit, road surface settlement is 1.13 mm,having no impact on highway safety.(3) The maximum subsidence area of the road is always in the nearest side of the foundation pit, as the excavation, the maximum subsidence of road surface growed,but the increasing rate decreased.(4) Along with the excavation, the settlement of the road scope expands continually, the influence of excavation to 4 m deep range of 10.8 m, the influence of excavation to 13 m deep range of 28.58 mm. After the excavation to the final settlement the influence scope covers the whole road, but its main influence scope is 32 m, farther the distance of the development of the settlement was negligible.