Composite steel columns to EC3 and EC4: Theory, uses and practical design studies

Concrete cover to steel compression members acts as a fire protection and assists in carrying the load and preventing the members from buckling about the weak axis. The two main types of steel-cased columns are

1. Rolled hollow sections (RHSs) filled with normal-weight concrete. 2. Totally or partially encased universal column (UC) or universal beam

(UB) sections with equal flanges (Figure 13.1). Other types of sections can be cased with concrete; see Figure 6.7.1 and Clause 6.7.1 of EC4.