UNIFIED EQUATIONS FOR SOLID AND HOLLOW CONCRETE-FILLED TUBE COLUMNS UNDER COMPLEX STRESS:CORRELATION EQUATIONS

This thesis is to obtain the basic form of the strength and stability capacity correlation equations of the concrete-filled steel tubular structures under complex stress through the theoretical derivation.It should be considered the role of the impact of hoop between the steel and concrete, analyzed and summarized the working performace and loading capacity of concrete-filled steel tubular structures subject to respective axial compression, bending, shear and torsion.It will be introducted a hoop influence coefficient to adjust the various ultimate bearing capacity of items, so as to get a practical calculation formula for the compression, flexural bearing capacity which can be in good agreement with experiment and finite element values.This practical formula considering the role of the impact of hoop will replace the correlating equation to adjust the carrying capacity to finalize the expression of the strength and stability capacity correlation equations of the concrete-filled steel tubular structures under complex stress.