Study On The Plate Buckling And Width-thickness Ratio Of T Section Steel

The T-section steel which is cut lengthways from hot-rolled H steel is widely used because of it's high quality. The national steel structure design code (GBJ17-88) is notpermitted the b/t exceed (10 + 0.1) 235/fy . The width-thickness ratio of the web (b/tfor short) exceed the limitation often. So to decide if the T-section steel can be used in structure is a urgent problem.Theory deduce, experimentation and Finite Element Analysis(FEA for short) are carried out on b/t ratio of T-section steel. Theory analysis in this paper pointed out that the flexural-torsional buckling is the usual form of T-section steel. So the slenderness ratio of flexural-torsional buckling should be used when people give out the b/t ratio by the "equal stability" conception. Initial stress, defects and tangent modulus are include in the deduce of the paper to get a rational b/t ratio. Experiment is carried out to verify the theory of this paper. What's more much FEAs are carried so as to deduce a formula to see if the theory is correct. At the end of this paper a new formula is given as (4 + 0.27 yz) ( 45 yz 110 ), which can be used for revising steel structuredesign code.