Analysis About The Influence Of The Crossing-river Tunnel Construction In Harbin On Soil Body Stability

With the development of society, all kinds of resources, especially theland resources are in short. So the exploitation of underground space becomesmore important in 21 centuries, and all the countries around the world areworking at developing the underground building strongly. At the meantime,with the rapid development of our country's economy, more and morefacilities such as underground tunnel, underground piping and underpass arebecoming an indispensable part of peoples' life. So nowadays, it is one theimportant subject we faced with to solve the problems of undergroundengineering.Because of the importance of the crossing-river tunnel project which isdesigned to solve the problem of north-south transportation of Song huajiangin Harbin, how to carry on the construction and which method should beselected in construction have to be studied. The problems of soil bodystability which may be occur in two kinds of construction methods arediscussed in this paper, which is benefit for the choice of proper constructionmethod.The influences on the stability of tunnel surrounding soil body during theconstruction course using two kinds of methods (the shield method and thesubmerged tube method) are studied. What the shield method investigate arethe surface settlement amount, settlement range and its distribution regulation.On the basis of numerical simulation calculation of FEM, it is found that thesurface scope that is destroyed during the progress of construction is limit,that the surface settlement at the distance of 1.5 time tunnel diameter won'taffect the safety of surface soil body, that there is a smaller settlement amountwith the largest amount 4.85cm, and that the amount of settlement reduceswhit the distance to the tunnel center line. What the submerged tube methodinvestigates is the stability of underwater slop body after digging. Accordingto calculation, it is discovered that the slop stability coefficient becomes bigalong with the ratio of slop becomes small, but at the same time thedeformation and failure district of soil body becomes bigger. It is also foundthat the failure of underwater slope first occurs at the bottom of the slope,differing from the failure style of common slope, which should be noticed.The problem of soil body stability in tunnel construction is discussedfrom the following four parts: The item chosen basis, study content, schemeand technique routes of this paper are introduced in Chapter One. Secondly,the influence of shield tunnel construction on soil body stability is analyzed inChapter Two. The settlement deformation of surrounding soil body in thecourse of shied construction is modeled by the means of FEM, and thestability of soil body is studied. Emphases are put on the deformation range,settlement amount and the deformation distribution regulation. Thirdly, theinfluence of submerged tube tunnel construction on soil body stability isanalyzed in Chapter Three. The deformation failure of slope in the course ofsubmerged tube construction is simulated numerically, and the stability ofslope with different ratio is calculated. Finally, conclusions are drawn inChapter Four. According to the numerical simulation results, comparing thestability of soil body in different construction method, the suggesting ofconstruction method should be adopted in Harbin is put forward.