A state-of-the-art review on cold-formed steel roof truss system

The roof truss is an important structure to keep a building safe, protect it from rain and sunshine, and protect home appliances and equipment inside it. The stability of the roof truss system, either by using timber or steel, is necessary to study and investigate. The roof truss material, member section, configuration, connection or fastener, end support and span must be checked. Nowadays, cold-formed steel (CFS) with numerous advantages is selected as chord and web truss. However, the failure of CFS, such as buckling, must be revised to ensure that the CFS roof truss is stable. From the observations of previous research studies, the failure of the CFS roof truss has been broadly discussed and to determine the causes of stability. The effect of CFS truss mainly fails or become unstable due to a slender section of the truss, especially on the compression member. Intentionally, the slender section of the top chord must be replaced with a short section or changed to become a curved section. The idea is to certify the local buckling failure of the top chord and prevent the nearest section from failing. Finally, the guideline for checking the stability of the CFS roof truss was established to give an experience for engineers