Taking　Zhoutouzui　Immersed　Tunnel　as　an　example,　finite-infinite　element　model　of　immersed　tunnel-joint-soil　is　developed.　Through　numerical　calculation,　dynamic　response　of　the　tunnel　and　its　joints　is　studied　in　detail　under　different　joint　stiffness.　The　objectives　of　these　researches　are　to　provide　strong　technical　support　for　immersed　tunnel　projects　in　China,　provide　theoretical　and　experimental　basis　for　revision　of　the　seismic　code,　accumulate　information　to　establish　the　analysis　theory　and　design　method,　and　understand　the　possible　damage　mechanism　of　underwater　tunnel　structures.　©　2017　American　Society　of　Civil　Engineers.