Seminar - Demao Yang- Compression stability of high strength steel sections with low strain-hardening

Wednesday, September 6, 2000, 3 - 4 pm
Civil Engineering Lecture Room 3

Abstract

The use of high strength steels with yield stress values up to 550 MPa is increasing rapidly. However, high strength steels usually have little or no strain hardening in the stress-strain curve, and low ductility. Therefore, the standard AS/NZ4600 for cold-formed steel structures and the AISI specification for cold-formed steel structural members have limited the design stress for high strength steels to 75 percent of their yield stress or tensile strength as applicable, mainly due to the lack of knowledge of their structural behaviour in compression.

So, there is an urgent need to investigate the stability of steels of this type when formed into sections and subject to compression in order to utilise high strength steels economically.

At the first stage, many stub columns tests have been done. The test specimens were fabricated form cold-reduced G550 high strength steel sheets with a range of box shape sections and were tested between fixed ends on the Sintech machine. Some results have been obtained.