Aluminum tubular sections subjected to web crippling - Part I: Tests and finite element analysis

A series of tests on aluminum square and rectangular hollow sections subjected to web crippling is presented. A total of 150 web crippling tests were conducted. The web crippling tests were conducted under two loading conditions of end-two-flange (ETF) and interior-two-flange (ITF). The concentrated load was applied by means of bearing plates, which act across the full flange width of the specimen sections. Different bearing lengths were investigated. The test specimens were fabricated by extrusion using 6063-T5 and 6061-T6 heat-treated aluminum alloys. The test specimens consisted of normal strength material (T5) with the 0.2% tensile proof stress (yield stress) ranging from 185 to 196MPa, and high-strength material (T6) with the 0.2% tensile proof stress ranging from 226 to 317MPa. The measured web slenderness value of the tubular sections ranged from comparatively stocky webs of 6.3 to relatively more slender webs of 74.5. The effect of the 0.2% proof stress and bearing length on the web crippling strength (capacity) of aluminum tubular sections was investigated. In the literature, little test data are available on aluminum members subjected to web crippling. The web crippling test results obtained from this study are valuable for the development of design rules. A nonlinear finite element model (FEM) is developed and verified against the test results. The geometric and material non-linearities were considered in the FEM. It is shown that the FEM closely predicted the web crippling strengths and failure modes of the tested specimens. (C) 2007 Elsevier Ltd. All rights reserved.