The airport building has 36 reinforcement concrete structure hollow giant-scale columns which have different heights and cross-sections.

7,the hysteretic behaviors of mega steel columns braced with inversed V shape bracings and X shape bracings are studied with some influencing factors,including loading modes,axial compression ratios,slenderness ratios of braces,axial stiffness of braces,and stiffness of beams.

7,the hysteretic behaviors of mega steel columns braced with inversed V bracings and X bracings are studied under the action of different axial compression ratios.

Using dual non-linearity analysis program,the numerical simulation of the coupling relationship between forces and displacements in spatial orthogonal directions are carried out,and the effect manners of loading modes on the spatial hysteretic behavior of mega steel columns are obtained.