Study On Disturbance Law And Safe Distance Of Rectangular Pipe-Jacking Cable Tunnel In Soft Clay Caused By Adjacent External Construction

China has a vast territory,there are a variety of geological structures and soil types,which also allows many special construction methods to be carried out in China.As a construction method suitable for soft soil and water rich soft soil,pipe jacking method is widely used in various soft clay areas.The pipe jacking method includes circular pipe jacking construction and rectangular pipe jacking construction.In the early stage of this topic,it mainly discusses the related proble ms of disturbance and disturbance in the circular section pipe jacking construction.As a commonpipe jacking section form,rectangular pipe jacking is also widely used in various projects.Therefore,this paper probes into the disturbance problem of existing rectangular pipe jacking construction in soft clay area,and mainly studies the influence of disturbance.The contents and achieve ments are as follows:The results show that: after the completion of rectangular pipe jacking construction,the stress distribution is very different from that of circular pipe jacking.The main perfor mance is that after the completion of circular pipe jacking construction,the stress is relatively uniform,while the rectangular pipe jacking tunnel will produce stress concentration at the corner,and the size of rectangular pipe jacking section is the main factor affecting the stress.The vertical defor mation of soil is affected by pipe jacking,and the defor mation curve is discontinuous,and the position above the pipe jacking rises,and the closer the pipe jacking is,jacking are no longer symmetrical,and the stress of the pipe jacking near the foundation pit will be slightly less than that far away from the foundation pit.The disturbance law of static pile driving on existing rectangular pipe jacking.The main conclusions are as follows: during the construction of static pile driving,a part of the upper soil is carried to the lower part by the pile,so that the upper soil is in the unloading state,and the lower soil is in the squeezing state due to the increase of the number of soil particles.Therefore,on the side near the pile,the circu mferential and radial stress of the upper part of the pipe jacking beco mess maller,while the stress of the lower part of the pipe jacking becomes larger;co MPared with single static pile driving,the pile form is more steady.The disturbance range of rectangular pipe jacking leaded by structure is extensive and the effect degree is deeper.Based on the numerical si mulation of vibration pile driving construction process,the main disturbance law of vibration pile driving on existing rectangular pipe jacking is studied.The main conclusions are as follows: the vertical defor mation of the existing rectangular pipe jacking tunnel is much greater than the horizontal deformation during the construction of vibration driven pile;si milar to the static pile driving,the stress of the upper pipe jacking near the pile side is less than that of the opposite side;co MPared with the static pile driving and the vibration driven pile with the sa me dia meter and distance,the vibration driven pile construction has less disturbance on the existing rectangular pipe jacking bigger.