Areas Formerly Flooded By The Huanghe River Flyover Cap Of Foundation Pit Excavation On Both Impact On The Stability Of Roadbed

At present, network-like horizontal and vertical line was crossed, resulting in new roads or under must wear during the cross-line design, leading to many overpass caps must close high fill embankment slope layout. The excavation pit caps will lead to roadbed original mechanical equilibrium is destroyed, and the seepage pit road vehicles on both the dynamic load and high groundwater levels will be increased due to the risk of excavation damage, exacerbating the loss of subgrade chance of stability. The project site monitoring by collecting data, consider pit seepage and embankment overload role for the stability of embankment and excavation carried out the analysis.according to theoretical calculations and field monitoring results analysis, the following conclusions:1) Excavation stage pit when far away from the embankment toe, lateral displacement of a large shallow soil; when the distance near the embankment toe, the deep soil lateral displacement volume increased significantly. Pit pile pulling stage in lateral earth pressure, partial collapse occurred around the pit.2) the depth of excavation and embankment overload, the greater the amount of excavation and lateral displacement volume upheaval in the bottom, while the bottom of the embankment caused by an area of negative pore pressure increases, increasing the incidence of differential settlement of subgrade.3) In order to improve the stability of the existing embankment excavation next time, should be considered reasonable buried deep sheet piles and supporting way, and to strengthen monitoring of the construction site.