Consistency study on bearing capacity formulae in the Chinese 'Code for design of concrete filled steel tubular structures'

The latest national standard of the Chinese 'Code for design of concrete filled steel tubular structures' (discussion vision) was proposed based on the technical specifications of concrete filled steel tube (CFST) CECS 254: 2012, CECS 28: 2012 and CECS 159: 2004, etc. Because the formulae of the bearing capacity for CFSTs are from different technical specifications, which have different forms, their consistency need to be studies. In this paper, the calculation methods of bearing capacity for CFST with various cross-section shapes in the national standard are compared systematically. Diversity and consistency of calculation accuracy of bearing capacity calculation formulae and formula forms from different technical specifications are also analyzed. The results show that although there are some differences in bearing capacity formulas from different technical specifications, the essential rules are still the same and calculation precision is within the scope of engineering tolerance and on the safety side, which preliminarily demonstrate the consistency and rationality of the bearing capacity calculation methods of the national standard.