The Research Of The Application Of The New Segment Shield Tunnel Technique

With the consistent and rapid development of the national economy, and the speedup of urbanlization,big cities ,especially the extra big cities of which the economy is developed and the density of population is very high ,the pubulic transpatations are facing more and more problems and difficulties.Railway transportation system is the best method which is recongnized in the world wide.Having the advantage of safety,high quality and little affection to the buildings around,shield technique is applied abroad in the construction of metro,and has been the main construction method in metro tunnel.shield technique can be classified into segment seams in sequence ,segment seams in stagger and new type segement ect.The new type of segment shield can fit one whole tunnel or several tunnels with only one group segements in ring,it can reduce the amount of steel moulding board needed,improve the extent of mechanization in construction and reduce the cost of project,this is right the direction of shield tunnel development.Basing on the BAISHIZHOU-KEJIYUAN tunnel of the follow-up engineering in SHEZHEN METRO LINE 1,the author has researched and solved the core technique of the new type shield tunnel,such as the general plane and profile of tunnel,the section of new type segmen tunnel,the structure analyses and the deformation of tunnel,the technique of the key structure joint,the waterproof of tunnel and the consolidation of foundation ect,especially put emphasis on the structure analysis about new type segment tunnel:take beam-spring model to simulate the segment joints and the assembly effect between them,and get more accurate results finally.In the meantime ,considering the complicacy of the structure and the high frequency of engineering accident about the connecting passege and the pump house between two tunnels,the anthor use 3D FEM model to analyze the structure,and put forward the new viewpoint that safety is the most important factor in the selection of construction method for such structure joint.