Considering　the　effects　of　seepage　and　dynamic　pressure,　defining　a　rock　mass　as　a　saturated　porous　media,　and　using　the　finite　element　method,　a　dynamic　fluid–structure　interaction　model　of　a　subsea　tunnel　with　a　viscous　spring　artificial　boundary　is　established.　Adopting　rubber　and　foam　concrete　as　shock　absorption　layers　and　inputting　both　horizontal　and　vertical　earthquake　waves,　the　time　history　curves　of　the　first　principal　stress　at　key　points　in　the　secondary　lining　structure　are　comparatively　analyzed　based　on　the　presence　and　absence　of　shock　absorption　layers.　The　principal　stress　peaks　are　also　analyzed.　The　damping　effect　of　the　shock　absorption　layer　is　studied.　The　results　show　that　the　peak　and　principal　stresses　at　the　main　parts　of　the　tunnel　lining　structure　decrease　after　the　shock　absorption　layer　is　established.　Obvious　decreases　occur　in　the　vault　and　inverted　arch.　A　certain　degree　of　peak　stress　reduction　is　also　observed　after　the　shock　absorption　layer　is　established.　Establishing　the　shock　absorption　layer　does　not　change　the　spectrum　characteristics　of　the　tunnel　structure.　Foam　concrete　shock　absorption　is　recommended　because　the　damping　effect　of　foam　concrete　is　more　observable　than　that　of　rubber.　©　2019,　Springer　Nature　Switzerland　AG.