Experimental Testing of Centrically Compressed Cold-Formed Steel Members with Web Holes

In this paper, the experimental investigation of centrically compressed cold-formed steel members with web holes was outlined. Compression tests were conducted on 4 columns with two web holes and 4 columns with three web holes. Furthermore, two different cross-sections were taken into account. Hinged boundary conditions around major bending axis of tested elements were designed in order to achieve the desired type of connection with the testing equipment. With the aim of proper definition of material behavior and initial geometric imperfections of tested elements in subsequent numerical analyzes, material testing and geometry control were carried out prior to the experimental tests. Material tests were performed on flat and corner coupons, while the non-contact geometry control was conducted using the optical 3D scanner. For each type of specimens, nonlinear shell finite element simulations were carried out, providing good agreement with the experimental results. The failure of tested specimens is manifested mainly due to local, distortional or flexural buckling, occurring almost instantly, without prior warning. However, the pre- and post-buckling behavior slightly differs, depending on the members’ type of cross-section, which could be attributed to the different buckling load ratio around the two cross-sectional axes of the tested specimens.