Based　on　the　numerical　simulation　method　and　the　field　measured　data,　the　law　and　computational　method　of　the　ground　surface　settlement　initiated　by　the　excavation　of　the　double-line　tunnel　located　in　the　upper-soft　and　lower-hard　stratum　are　studied.　The　results　show　that　after　the　completion　of　the　tunnel　excavation,　the　lateral　settlement　curve　of　the　ground　surface　is　asymmetrically　distributed.　The　ground　surface　settlement　above　the　preceding　tunnel　is　larger　than　the　ground　surface　settlement　above　the　rear　tunnel.　During　the　excavation　of　the　double-line　tunnel,　the　location　of　the　maximum　settlement　of　ground　surface　gradually　moves　from　the　centerline　of　preceding　tunnel　to　the　direction　of　the　rear　tunnel,　and　the　settlement　mainly　occurs　before　the　trailing　tunnel　crosses　the　monitoring　section.　The　numerical　simulation　results　indicate　that　the　depth　and　spacing　of　the　tunnel　significantly　influence　the　ground　surface　settlement.　Therefore,　the　influence　of　tunnel　depth　and　tunnel　spacing　on　ground　surface　settlement　is　recommended　to　be　fully　considered　during　tunnel　design　stage.　In　addition,　the　non-linear　fitting　analysis　of　orthogonal　experimental　results　presents　that　the　parameter　i　in　the　calculation　formula　of　ground　surface　settlement　is　independent　of　the　tunnel　excavation　order,　and　the　maximum　settlement　ratio　γ　decreases　slightly　with　the　increase　of　tunnel　spacing.　When　the　staggered　distance　of　the　excavation　is　within　the　longitudinal　influence　range　of　tunnel　excavation,　γ　has　a　little　change.　Accordingly,　the　parameter　γ　is　introduced　to　improve　the　calculation　formula　of　ground　surface　settlement　for　double-line　tunneling　scenarios,　and　the　calculation　formula　is　validated　by　comparing　the　calculated　results　with　the　measured　data.　©　2019,　Science　Press.　All　right　reserved.