ABSTRACT
The relationship between the cross-sectional area (A) and the radius of gyration (r) is determined for CHS, SHS and double-angle sections. The required A is calculated in function of compressive force N. The A - N diagram shows the weight savings achievable by using CHS or SHS instead of double-angle sections. An illustrative numerical example of a roof truss shows the significant differences among the volumes of trusses constructed from CHS, SHS and double-angle sections. The optimal slope of the upper chord giving the minimum volume of truss depends on the type of cross-section of compressed struts.
