Based　on　the　Taiyuan　subway　tunnel　project　crossing　through　an　active　fault　zone,　this　paper　utilizes　ABAQUS　software　to　construct　a　three-dimensional　refined　model.　The　model　aims　to　investigate　the　mechanical　behaviour　and　fault-resistant　design　methods　of　urban　shallow　subway　tunnels　that　cross　normal　faults.　Using　numerical　simulation　and　mathematical　induction,　the　study　explores　the　impact　of　two　primary　factors,　namely　fault　dip　angle　and　fault　displacement,　on　the　mechanical　response　and　damage　degree　of　the　subway　tunnel　structure.　In　addition,　ellipticity　is　employed　to　unveil　the　spatial　deformation　characteristics　of　the　tunnel　cross-section.　The　findings　indicate　that　due　to　normal　fault　dislocation,　the　lining　structure　deflects　at　a　specific　angle　to　adjust　to　the　fault’s　forced　displacement.　This　results　in　local　segments　of　the　structure　becoming　de-hollowed　and　out　of　sync　with　the　soil　layer’s　movement.　Secondly,　the　hanging　wall’s　damage　area　and　stress-strain　exceed　that　of　the　footwall　by　several　times.　Thirdly,　the　tunnel　deformation’s　maximum　position　depends　on　the　fault　dislocation’s　location.　The　implementation　of　segmental　lining　mitigation　measures　notably　diminishes　the　detrimental　impact　of　fault　displacement,　ultimately　leading　to　a　reduction　in　both　the　magnitude　of　destruction　and　the　affected　area　of　the　tunnel　structure.　©　2024　The　Author(s).