Analysis Of The Impact Of The Settlement Of The Composite Foundation In West Jinan Railway Station Of Beijing-Shanghai High-speed Railway After Pumping Water

Recent years, with the expansion of the scale excavation, groundwater problems is encountered more and more frequently. The most effective and economical way of controlling groundwater is reasonablely dewatering, however, dewatering bound to have the engineering properties of soil and a great impact on the surrounding environment. In view of the immaturity of the effect of the settlement of the compsiste which is in large station after pumping water, this paper, basing on monitoring data, theoretical analysis and numerical simulation results, summed up the impact of the settlement of the compsiste after pumping wate. Corresponding study achievements are presented as follows:First, the impact of dewatering is different on various length pile on the same cross-section of composite foundation, and the longer pile length is not appreciably affected. 35m PFG pile area is affected less than 25m CFG pile area, and 25m CFG pile area is affected less than 15m CFG pile area. The variable length Pile region is affected more appreciably than non-variable length pile region.Secondly, Settlement of deep embankment is appreciably affected by dewatering, the Soil above the groundwater level is affected most appreciably, and the reinforcement area is affected more appreciably than the underlying soil.Tirdly, dewatering has greater impact on the earth among pile than the pile. The settlement of earth among pile is significantly fluctuant, and this shows that piercing effect of pile is obvious after dewatering.Forthly, the impact of dewatering is different on pore water pressure of different depths.Dewatering has greater impact on pore water pressure of reinforce area than one of subjacent bed.Lastly, foundation pit stop will have an impact on the composite foundation, and composite foundation whose settlement is almost stable has the rebound phenomenon.