The Calculation Method of Axial Force in the Calculation of the Boom Tower Crane Stability

The concept of equivalent stiffness and equivalent negative stiffness is introduced in this paper, established the equivalent relationship between the force acting on the middle of variable cross-section column and the force acting on the top of constant cross-section column on boom tower crane lifting plane and slewing plane by the equivalent stiffness law and the equivalent negative stiffness method, The force on the middle of column is converted into the force on the top of column by the equivalent relationship.