During the construction of shie ld tunnels，support pressure is usually applied at the work face to prevent BE:HO^-.1
excessive tunneling—induced soil movement or collapse．However，the selection and control of appropriate support 7 \rz*
pressure is difficult due to variation of soil conditions and uncerlainty in construction．Support pressure should be ?^Q!=W<7
controlled SO that it is not SO low as to cause face collapse and not SO high as to induce ground hogging．Numerical 4E J
simulation is employed to study how the soil parameter and ground water affect the support pressure，and to give the Aj;Z
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proper support pressure at the excavation face in a case study． {2}O\A
Keywords：shield tunnel；excavati‘on face；numerical solution；support pressure
