A　unified　displacement　function　is　used　as　the　displacement　boundary　condition　of　the　cross-section　of　each　tunnel,　which　can　be　used　to　capture　the　asymmetrical　deformation　behaviors　about　the　horizontal　and　vertical　center　line.　Complex　variable　method　is　adopted　to　obtain　the　analytical　solution　of　a　single　tunnel.　Based　on　the　Schwartz　alternating　method,　the　analytical　solution　of　twin　tunnels　is　obtained　and　the　correctness　of　the　analytical　solution　of　twin　tunnels　is　verified.　A　series　of　analyses　are　carried　out　to　investigate　the　effects　of　the　displacement　boundary　condition　of　the　tunnel　cross-section　and　the　distance　of　twin　tunnels　on　the　ground　surface　settlement　trough　curve　and　the　ground　displacement　field.　Based　on　the　proposed　method,　the　parameters　of　displacement　mode　of　the　cross-section　of　twin　tunnels　are　calibrated　through　field　monitoring　data　of　the　Bangkok　Subway　Tunnel　project,　and　the　displacement　field　of　the　whole　ground　are　analyzed.　The　proposed　method　can　provides　guidance　in　the　conceptual　stage　of　the　design　process　of　twin　tunnels.　(C)　2018　Elsevier　Inc.　All　rights　reserved.