BIM Aided Structural Analysis of Steel Buildings

This dissertation addresses the behaviour of connections in steel framed buildings by developing different levels of analysis that are facilitated by the use of several structural software with various capabilities. Nowadays, structural design is performed by considering either rigid or pinned joints, despite several studies have revealed that many joints present a semi-rigid behaviour. The increasing availability of BIM software provides the tools needed to perform a more refined analysis. Taking into account the importance of the joints behaviour on the structure, a new methodology is proposed to perform more accurate structural analysis with the help of BIM as the link between analysis, design and fabrication phases.

The starting point of the process is the structural model, in which the connections are considered as rigid or pinned. The model is then exported to Tekla Structures by using IFC and plug-ins to detail the connections. Tekla Structures BIM Link is used to synchronize the calculation of the metallic connections with IdeaStatiCa, in order to perform safety verifications and assess their stiffness. Considering the results obtained in IdeaStatiCa, the frame partial fixity springs are modified in Etabs and a redesign of the structure is performed. From the structural analysis software, results like internal forces, modes of vibrations and drifts are obtained, and from the BIM software results like quantity take-off are collected.

The developed methodology is applied to the analysis of industrial steel buildings with moment resisting frames in the frame plane and concentric bracings in the perpendicular direction. The results are confronted with those obtained from an analysis without the consideration of semi-rigid joints and from an analysis considering joint stiffness as prescribed in EN 1993-1-8:2005 and AISC 360-16. Final remarks and recommendations about the process of using BIM are presented in the conclusions.