Three　types　of　Z-type　cantilever　beam　splices　of　the　column-tree　connection　have　been　designed,　which　dissipate　energy　through　plastic　hinges:　weakened　beam　splice,　beam　splice　with　a　reduced　beam　and　beam　splice　with　a　reduced　cantilever　beam.　The　weakened　beam　splice　mainly　dissipates　energy　through　slipping,　the　beam　splice　with　a　reduced　beam　utilizes　the　slip　of　the　splice　and　plastic　deformation　of　the　reduced　beam　section　to　dissipate　energy,　and　beam　splice　with　a　reduced　cantilever　beam　mainly　utilizes　plastic　deformation　of　the　reduced　cantilever　beam　to　dissipate　energy.　The　behavior　of　three　types　of　beam　splices　of　the　column-tree　connection　is　investigated　and　discussed　based　on　both　tests　and　finite　element　analyses.　The　results　show　that　the　three　types　of　specimens　have　good　ductility　performance　and　plastic　rotation　capacity.　The　energy　dissipation　capacity　of　the　beam　splice　with　a　reduced　cantilever　beam　is　better　than　that　of　the　weakened　beam　splice.　The　energy　dissipation　capacity　of　the　beam　splice　with　a　reduced　beam　section　is　between　the　two　splices.　Simplified　computation　formulas　and　seismic　design　requirements　for　beam　splices　are　proposed,　and　the　computation　results　are　in　good　agreement　with　those　of　the　experiments.　(C)　2017　Elsevier　Ltd.　All　rights　reserved.