LAUSR

Abstract The continuous-supported multi-column walls have already been used in modular steel buildings (MSB). Therefore, using two full-scale specimens, the current study evaluated the axial behaviour of planar multi-column walls with structural hollow sections (SHS). Then, a 3D finite element model (FEM) was created and validated to study the individual column and boundary support effects on each column. Prediction equations in EC3, AISC360, and GB50017 were then used to predict the ultimate compressive resistance of columns in walls. Because of the elastic buckling, the current slenderness limit for Class 3 steel cross-sections becomes less conservative. The boundary support effect enhances external columns rigidity and capacity than other columns, leading to instability. FEM provides reasonable estimates of the compressive behaviour of walls and each column. Each column exhibits distinct load distribution, confirming that the assumption of uniform load distribution among columns is unacceptable for multi-column modular walls. The prediction equations showed that GB50017 was safer than the EC3 and AISC, while EC3 was the least secure. Hence, the current study concluded experimental, numerical, and analytical findings to evaluate the axial behaviour of multi-column walls in multi-storey MSBs.