Axial Capacity of Back-to-Back Built-Up Aluminum Alloy Channel Section Columns

Abstract

An experimental investigation of 12 screw-fastened back-to-back built-up aluminum alloy slender columns under axial compression is presented, complemented by a numerical finite element study comprising 246 results. Using a laser scanner, the geometric imperfections were measured. In the numerical study, the effect of the modified slenderness, number of screws, and section thickness were investigated. Axial strengths obtained from the tests and finite element (FE) were used to assess guidance given in the Aluminum Design Manual (ADM 2020), Eurocode9 (CEN 2007), Australian/New Zealand Standards (AS/NZS 2018), and American Iron and Steel Institute (AISI 2016) standards. The ADM 2020 and CEN 2007 were found to be conservative by 30%. However, AISI 2016 and AS/NZS 2018 were found to be more accurate relative to the test and FE analysis results and shown to be conservative by 5%.