Experimental analysis of cold-formed steel c-sections with the notch subjected to axial compression

Abstract

Studies on the use of cold-formed steel (CFS) C-section, which is a civil engineering material, in building and civil engineering work are still on-going. The advantages of the CFS C-section are becoming so interesting that it is often being used as a roof truss system, storage rack, and wall framing. In order to have a roof truss system with a strong, safe, and stable condition, a study on truss member was carried out using the cut-curving process. Before the CFS C-section was curved, the process started by cutting the section in a proper way. A parametric study was conducted to determine the suitability of the cut pattern which recognised as a notch in the section and find out whether or not the notch depth would affect the ultimate load of the CFS C-section column. The study of CFS C-section was separated into two parts; firstly, to investigate the mechanical behaviour of the column in different notch depths and secondly, to investigate the behaviour in different column height with fixed notch depth. The notch width of 3 mm and notch spacing of 100 mm for both parts were fixed. Total specimen for both parts were 15 specimens. The results of the study showed that the reduction of the ultimate load was about 56–65% of the variation of notch depth section when compared with the normal section. Therefore, the ultimate load of the section with the notch decreased when the notch depth increased. In addition, the study illustrated that the reduction of the ultimate load was 64–82% of the variation of column height between 100 mm to 500 mm. Finally, the average percentage of the column height was 72% which can use in the modification of CFS C-section without notch to CFS C-section with notch calculation.