Effect of screw distance on combined profile cold form steel in increasing the compression member capacity

Abstract

The use of cold-formed steel (CFS) as a frame in a single-story structure building system has been widely applied. However, the use of cold-formed steel for multi-story buildings is still constrained in the structure system, especially column. In the conventional structure, columns used in large dimension, height, h> 150 mm and thickness, t> 1.2 mm which makes the construction cost expensive. An innovation of cold-formed steel combine profile into one compression member unit is very interesting to study, furthermore, previous research provides information on a variety of cold-formed steel behaviors with small dimensions of height, h <150 mm and thickness, t <1mm, which can be developed into columns with greater strength. There have been a lot of research on behavior on cold-formed steel, but the study on screw optimization especially on combined profile to become compression member still need to develop. From the compression test on double profile back to back and flange to flange length, l = 300 mm and screw distance variation, 25 to 150 mm with 50 mm intervals, indicating a response similarity at screw spacing 25 mm, 50 mm and 75 mm, while the screw distance 100 mm, 125 mm and 150 mm experienced backline capacity.