Research On Deformation Of The Ground Foundation Adjacent To Excavation In The Water-rich Area

In recent years,more and more pits have to built adjacent to the existing buildings due to prosperous construction,the accidents occurs more ordinary.What’s more,the present study is mainly focused on the deformation effects of the excavation on the adjacent buildings with no account of the influence of the groundwater.Further study on the settlement of the foundation and ground adjacent to the excavation is necessary.For this purpose,the results of the field observation have been analyzed.we have established two 3-D finite element models while considering the solid-fluid coupling and non-solid-fluid coupling with the help of a simulation software known as Midas-GTS by taking the DingZhou foundation pit as a case study sample.And the results have shown that:(1)The area far away from the excavation is less dangerous to the area adjacent to the excavation.The seepage and consolidation in accordance with the measured data and information,which can reflect the deformation data status-in-situ of the foundation pit so as to guarantee the construction quality effectively.(2)we have worked out the numerical results of the ground settlement,the foundation settlement,the deformation and the mechanical features of the pile,respectively,through comparing the results under the above two conditions.Besides,the correlated data of the field has been monitored to verify the accuracy of the calculation models.(3)The results of the above-mentioned analysis and simulated study have shown that,the ground foundation settlement and the pile deformation in the solid-fluid model proves less serious as expected in the non-solid-fluid model,and,so is the stability of the solid-fluid model.Therefore,it is unreasonable to say that the effects of the groundwater are neglected in the excavation practice.(4)The distance between the foundation and the foundation pit has a great influence on the surface settlement curve.With the increase of Lmin,the maximum value of surface subsidence decreases and the maximum settlement point position gradually away from the foundation pit wall.The variation trend of the subsidence curve of the foundation pit gradually changes from "V" to saddle with the increase of Lmin.(5)The location and the shape of the foundation themselves have great influence on its settlement.And,in fact,the bigger the raft foundation area is,the shorter the distance away from the excavation is,and,in turn,the1.5~2 the height of the foundation would be.Besides,the asymmetric distribution in the geometry and the dewatering activities of the excavation tend to make the foundation settlement more and more uneven and unbalanced,which may in turn aggravate the unbalanced settlement or instability.