The weaken technique of bending moment for support beam of internal climb tower

Abstract This paper develops a new analysis method to weaken bending moment at the end of support beam of the inner climbing tower crane. Firstly, the equivalent length of the variable cross-section beam is calculated according to the principle which the angular displacement of the variable cross-section beam is equal to that of the equal cross-section beam under the action of the unit bending moment. Then, the deformation of the variable cross-section can be calculated by using the calculation formula of the equal cross-section beam. Finally, Graphic multiplication is used to solve the stepped variable cross-section statically determinate beam and the function relation between bending moment and inertia moment ratio and variable cross-section length ratio is obtained by MATLAB. It is of great significance to the thin-walled supporting and protection by using the function between the bending moment and the parameter to determine the optimal supporting main beam.