Abstract In order to study the influence of shield tunneling with tunnels followed by well excavation on segment opening,under the precondition that it cannot easily be measured and tested,an elasto-plastic simulation is carried out with FEM program to analyze segment opening caused by the tunnels followed by well excavation. In combination with the typical engineering example,the influences of mechanical properties of soil,local reinforcement soil and groundwater level are discussed. The results indicate that influencing scope is mainly in five segment length near the continuous wall of work well,so analysis of seepage control during the construction should consider emphatically four joints near the work well. Segment opening is strongly impacted by the soil stiffness and it decreases with the increase of stiffness. Segment opening is not affected by soil strength index. It can use local reinforcement to effectively reduce the segment opening to prevent leakage of shield tunnel. The existence of groundwater above the segment has significant influence on segment opening,influencing scope is mainly in five segment length,but the water level has a tiny effect on segment opening. It suggests that it is necessary to perform local reinforcement in five segment length near the continuous wall of work well when adopting tunnels followed by well excavation to ensure the safety of tunnel.
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Received: 21 May 2013
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