Boundary conditions of steam tUrbine blade root is one of the fundament requirements for accurate calculation of blade vibration characteristicswhile Finite Element Method is used. In this Paper

under various root boundary conditions of a 323mm long blade with double T - shaped root

thesensitivity of blade vibration characteristics to the boundary conditions is studied by using a 3D -- 8 Node flute element model. some valuable conclu-sinns are drawn. One is that the blade vibration characteristics are sensitive to the boundary conditions of root tangential vertical surface

but notsensitive to the boundary conditions of root radial vertical surface. Some methods

which can be used to dcal with the boundary conditions and tosimulate the actUal contract conditions between blade root and rotor disk and between blade roots

are recommended.