How　to　estimate　the　seismic　response　of　shield　tunnels　reasonably　has　been　a　significant　issue　in　both　industry　and　academia.　Compared　with　the　transverse　seismic　response,　the　longitudinal　seismic　response　is　more　complex.　The　shield　tunnel　is　modeled　as　a　Timoshenko　beam　on　Winkler　foundations,　considering　both　residual　axial　force　and　additional　axial　force　due　to　longitudinal　seismic.　A　theoretical　model　was　presented　to　consider　the　longitudinal　and　transverse　stratum　displacements.　The　longitudinal　seismic　response　of　shield　tunnels　was　solved　using　the　finite　difference　method.　The　theoretical　model　and　calculation　method　were　validated　through　case　studies　of　stagger-assembled　shield　tunnels　with　a　6.2　m　diameter.　Considering　axial　force　increased　the　overall　stiffness　of　shield　tunnel,　resulting　in　decreased　internal　force　and　deformation　response.　The　proposed　method　was　degraded　to　the　traditional　one　when　the　axial　force　is　neglected.　The　influences　of　residual　axial　force,　seismic　wavelength,　seismic　incidence　angle　and　foundation　reaction　coefficient　on　the　longitudinal　seismic　response　were　further　explored.　With　the　increase　of　residual　axial　force,　the　overall　stiffness　of　shield　tunnel　increased,　and　the　peak　seismic　response　of　shield　tunnel　decreased.　When　the　incident　angle　is　less　than　45°,　the　influences　of　residual　axial　force　and　foundation　reaction　coefficient　on　the　peak　response　were　more　significant.　With　the　increase　of　the　foundation　reaction　coefficient,　the　tunnel　deflection　and　the　discontinuous　deformation　between　joints　increased.　Wavelengths　between　20　m　and　100　m　may　lead　to　greater　opening　and　dislocation　between　joints.　These　studies　can　provide　theoretical　support　for　the　longitudinal　seismic　design　of　shield　tunnels.　©　2024　Biodiversity　Research　Center　Academia　Sinica.　All　rights　reserved.