scope:

This document provides guidelines for the design, construction, and inspection of concrete-filled steel tubular (CFST) hybrid structures. They can be used as main structural components like columns, girders, piers, or arches in buildings, bridges, especially in high-rise structures, long-span spatial structures, and large-scale bridges.

CFST hybrid structures can employ CFST members with a circular cross-section as their chords, and they can also use square or rectangular CFST chords.

This document can be used as an alternative to the development of a national CFST hybrid structure standard, or equivalent document in countries where no national design standards are available by themselves, or as an alternative to the national CFST hybrid structure standard in countries where specifically considered and accepted by the national standard body or other appropriate regulatory organization.

This can be considered as a complementary design document in countries where the design of CFST structures is covered in national steel and/or composite structure standards, but specific design provisions of CFST hybrid structures included herein may not exist. It can also be considered as a design document for the design and construction of CFST structures in countries where no national design standards are available for CFST structures.