The　design　parameters　of　shed-pipes　of　Xiamen　Xiang＇an　sub-sea　tunnel　portal　are　presented　and　then　the　impacts　and　effects　of　shed-pipes　are　analyzed　by　fast　Lagrangian　analysis　of　continua　(FLAC).　The　key　technologies　of　shed-pipe　construction　are　summarized,　and　the　problems　and　solutions　in　the　construction　process　are　mentioned.　The　40　m　long　shed-pipes　combined　with　grouting　can　act　as　carrying　arch,　which　makes　the　distributing　of　ground　subsidence　uniform　and　can　control　the　maximum　settlement　effectively.　The　problems　of　stratum　disturbance,　which　caused　by　cyclic　medium　of　boreholes,　are　overcome.　The　shed-pipes　play　important　roles　for　tunneling　in　terms　of　safety.