In　view　of　the　face　stability　of　a　shallow-buried　shield　tunnel　excavation,　this　paper　investigates　the　problem　using　an　adaptive　finite-element　limit　analysis　combined　with　slip-line　theory.　First,　a　series　of　adaptive　finite-element　limit　analyses　are　conducted　to　explore　the　passive　failure　mechanisms　of　the　shallow-buried　shield　tunnel　face.　Based　on　the　characteristics　of　the　failure　mechanisms,　a　funnel-shaped　asymmetric　boundary　failure　mechanism　is　proposed.　Then,　a　mathematical　computational　model　is　established　using　the　slip-line　method,　which　considers　the　characteristics　of　the　passive　failure　mechanisms　and　the　stress　state　of　the　plastic　region　in　the　surrounding　soil.　The　formula　for　calculating　the　limit　support　pressure　for　the　passive　failure　of　the　shield　tunnel　face　is　derived　using　the　finite-difference　method,　and　the　passive　failure　mechanisms　of　the　face　are　analyzed.　Finally,　the　calculated　results　of　the　model　are　compared　with　existing　research　results　and　the　numerical　results　in　this　paper.　The　results　show　that　the　proposed　computational　model　could　accurately　analyze　the　face　stability　of　shallow-buried　shield　tunnels　and　might　have　wide　applicability　in　the　analysis　of　the　limit　support　pressure　and　failure　mechanisms　of　the　face　in　shallow-buried　tunnels.　©　2024　American　Society　of　Civil　Engineers.