The Study Of Inverted Arch Precasting Technology For Qingling Ultra-Long Railway Tunnel Under The TBM Constrction Conditions

The modern practice of tunnel construction proves: closing all the sections as soon as possible under the conditions of weak surrounding rock, is an important principle of designing & construction of tunnel, which can make the full function of the surrounding rock and the supporting, and stabilize the tunnels. The best method to achieve this principle is to build the inverted arch.The theory and practice proves: both the temporary inverted arch and permanent inverted arch can all be functioned in stabilizing the tunnel, improving the construction safety, and increasing the long-term stability and functioning of the tunnel.The precasting technology in underground engineering is the important trend to achieve the construction-factorilization, to reduce the cost and to increase the engineering quality. The precasted inverted arch adopted in the construction of Qingling Tunnel is the first time in the tunnel construction in China. This thesis based on this specific article, from the aspects of theory analysis, module experiment, site surveying and etc. do the thoroughly studies on the adopted precasted inverted arch. This thesis proves the reasonability of the precasted inverted arch and its design method, and finishes the result analysis of the calculation, module experiment and site survey.At the same time, this thesis also studies the function of the precasted inverted arch in the whole coating structure and the function of the precasted inverted arch in the IBM construction conditions.The results and suggestions concluded in this thesis, is good to promote the precasting technology in the design and construction works of railway tunnel.