Monitor and analysis of the foundation pit combination support of Jinan West Railway Station Ground

摘要

The foundation pit of Jinan West Railway Station Ground is vast in area and large in Excavating depth and closely adjacent to the high-speed railway buildings and subgrade, therefore the foundation pit's deformation is strictly controlled. The foundation pit supporting design applies a comprehensive mode by combing soil nailing wall, compound soil nailing wall and bored cast-in-situ piles with anchor cables. Monitoring has been carried out on internal force of side slope and supporting structure throughout the excavation of foundation pit, so detailed monitoring data have been acquired. It has been acquired, by contrastively analyzing, that since the foundation pit's displacement volume may reach about one half of the final displacement volume at the time when its excavation is completed, with a huge rate of change, supporting should be timely completed during the excavation period. Compound soil nailing wall can reduce side slope's horizontal displacement volume about 25～30%, compared with soil nailing wall, and effectively add the rigidness of side slope, however it is not very useful for settlement; We get utmost horizontal displacement volume at one third to two fifths of pile length, so it is advised to increase density and strength of anchor cables.