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Abstract: With the rapid development of national traffic construction, New Austrian Tunnelling Method has been applied to the construction of tunnel in China quickly. However, these make us suspect whether the support system consist of shotcrete, blotand steel gantry can guarneet the structure stablity of the tunnel. At the some time, whether the role of supporting measures to be brought into full playthis problem has great importance for the social and economic benefits.Conbine with Maoba tunnel, fistly, the principle of NATM tunnel, construction features, practical applications and so on were discussed. Introduced the monitoring of tunnel construction process and method of measurement, information feedback and prediction, measurement data processing and analysis were studied. Secondly, the elastic-plastic model is established by using the analysis software. The elastic-plastic model of Maoba tunnel wall rock is setted up by the software of FLAC3D. The results show that the variation of the displacement and stress is obtained accompanying the change of shotcrete, Anchor density, Bolt Length and the Steel Gantry when the rock and timbering after the spray-anchor are regarded as a whole. Through the above discussion, these make us to evaluate the stability of surrounding rock. At the same time, the advice of optimizing the initial anchor shotcreting is proposed so as to guide the construction purposes.
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