The　theoretical　model　of　twin　curved　shield　tunnels　and　refined　numerical　model　considering　the　characteristics　of　wedge-shaped　segment　ring　joints　were　established　in　this　paper.　Two　construction　schemes　of　taking　the　inner　side　or　outer　side　of　the　twin　curved　tunnels　as　the　first　tunnel　were　conducted　for　comparison.　Then　two　main　characteristics　of　curved　tunnel　construction　(over-excavation　and　yaw　excavation　loadings)　were　taken　as　variables　to　explore　their　response　to　the　approaching　construction　caused　by　unsynchronized　driving　of　twin　curved　shield　tunnels.　The　ground　surface　settlement　troughs　obtained　by　the　analytical　solution　and　numerical　simulation　are　in　good　agreement　with　the　monitoring　result.　On　the　condition　that　the　curved　tunnel　at　the　inner　side　is　taken　as　the　first　tunnel,　the　excavation　will　intensify　the　ground　settlement　and　the　internal　forces　of　its　segment.　In　the　case　that　the　overcutting　gap　is　not　of　large　volume,　it　is　advisable　to　first　excavate　the　curved　tunnel　at　the　outer　side,　and　then　construct　the　curved　tunnel　at　the　inner　side.　The　influence　of　soil　loss　on　the　ground　disturbance　is　greater　than　that　of　construction　loadings.　The　excessive　overcutting　gap　not　only　easily　induces　a　sharp　increase　in　the　ground　vertical　displacement,　but　also　may　lead　to　the　movement　of　soil　at　the　inner　and　middle　sides　towards　the　inner　side　of　the　curved　tunnels,　and　causes　the　soil　at　the　outer　side　to　move　towards　the　outer　side　of　the　curved　tunnels.　Remarkably,　excessive　overcutting　gap　may　lead　to　large　horizontal　displacements　of　the　ground　surface.