Finite Element Analysis (FEA) of Fabricated Square and Triangular Section Stub Columns Utilizing Very High Strength Steel Tubes

Abstract

This paper presents finite element analysis (FEA) of twenty fabricated square and triangular section (FSTS) stub columns utilizing very high strength (VHS) circular steel tubes with a nominal yield stress of 1,350 MPa. The VHS tubes are placed at each corner of the section and welded to Grade 350 steel plates. Two different nominal diameter-to-thickness ratios of 15.9 and 23.8 were chosen for the VHS tubes. Five different nominal width-to-thickness ratios ranging from 40 to 133 were chosen for the steel plates. Three different lengths of 500, 1000 and 1200mm were chosen for the specimens. The geometric imperfection and softening of heat – affected zone (HAZ) in the VHS tubes were included in the FEA along with material non-linearity and geometric non-linearity. The FEA results were compared with the experimental results and two analytical approaches proposed by the authors. Good agreement was found between the FEA, experimental and analytical results.

Keywords

finite element analysis stub columns fabricated sections high strength steel circular tubes geometric imperfection heat–affected zone non-linearity

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