Study On Surface Subsidence Law Of PBA Method Subway Station In Beijing Area

Beijing subway project construction is still in progress,including subway station as a subway transport personnel exchange place,must be close to densely populated areas.These places are often commercial bustling areas,surrounded by a variety of pipelines,tall buildings,the surface subsidence over the general assembly threaten the normal use of these buildings and safety.So it is important to control the settlement of the subway station.The PBA pile method is widely used in the construction of subway station because of its settlement control.However,the current research on PBA works is a theoretical study of practical experience,so study the surface sedimentation of PBA subway station in this paper.Based on the surface subsidence of the Meishuguan subway station,formula or method for the corresponding parameter of Peck empirical formula is puted forward in this paper.It can be used to describe ground surface subsidence rule of PBA subway station.Compared with the modified formula,it is found that the modified formula agrees well with the actual value,and the accuracy and generality of the formula are verified.In the end,the model of three cases was established using the FLAC 3D numerical simulation software,and the comparison analysis was carried out.In the process,the error of the value of a factor was discovered,and the reason was analyzed.Finally,the surface settlement curve of the modified formula after correcting the error is compared with the simulation condition,and it is found that it fit well and further prove the accuracy and generality of the modified formula.Finally,an empirical formula for describing the transverse settlement of the surface of the PBA subway station is obtained,and the settlement rules of the unknown station can be obtained by the corresponding parameters obtained from the known station.The formula should get more practical engineering verification,and for the PBA station ground subsidence research has some implications,in the actual construction process can help the project better control surface subsidence value.