Análise experimental de cantoneiras em aço inoxidável submetidas a compressão axial centrada

Abstract

Carbon steel rolled angles have often been used as a structural element without the alternative of another type of steel. This work aims to propose the study of the structural behaviour of a new type of steel, the stainless steel, which will be evaluated when subjected to axially centred compression. The structural element will be composed of a column of laminated profile L also known as angle bracket. Current stainless steel design standards are largely based on assumed analogies with the behaviour of carbon steel structures. For the understanding of the structural behaviour of the stainless steel, it was initially carried out experimental tests in carbon steel for three types of cross section 64x64x4,8, 76x76x6,4 and 102x102x6,4 with variable length from 272mm to 1517mm, the results were compared with the recommended calculation method in Eurocode 3, Part 1-1. This process was important to calibrate and validate the proposed experimental model. With the experimental process defined, the tests were started with stainless steel rolled angles with the same cross-sections of the carbon steel tests, however the length varied from 152mm to 1893mm. Finally, these results were compared with the calculation method proposed in Eurocode 3, Part 1-4. The ruin mode presented for laminated angles of less than or equal to 500mm in carbon steel and stainless steel was the local buckling of the corner flanges, for the 64x64x4.8 and 76x76x6.4 carbon steel angles the flexural-torsional buckling occurred in lengths equal to 750mm and with 945mm for the angle 102x102x6,4. In the other angles in carbon steel with length in the range of 1000mm to 1500mm the failure mode was flexural buckling. For the angles in stainless steel the failure mode was flexural-torsional buckling in the lengths between 500mm to 1480mm and between 147mm to 1893mm, flexural buckling. It has been found that the calculation criteria advocated by Eurocode 3, Part 1-1 and Eurocode 3, Part 1-4 are conservative and that the values of and λ_0 proposed by Eurocode 3, Part 1-4 are not valid for steel rolled angles stainless.