Based　on　settlement　monitoring　deformation　of　ground　surface　that　results　from　a　test　shield　tunnel,　the　characteristics　of　movement　of　ground　surface　are　analyzed,　and　several　qualitative　laws　are　obtained.　Using　professional　software　to　model　deformation　curve　of　ground　surface,　it　can　be　found　that　the　trough　profile　is　similar　to　normal　distribution　(namely　Gauss　distribution).　Finally,　a　comparison　between　fitting　results　and　previous　experienced　formulas　is　made,　and　a　good　agreement　can　be　obtained.