Maura Lecce

BASc MASc (University of Toronto)
PhD Research Student
Centre for Advanced Structural Engineering

Supervisor: Prof Kim Rasmussen
Associate Supervisor: Prof Greg Hancock

Stainless steel structural members are typically chosen for environmentally sensitive structures and offer a clean, long-life and aesthetically pleasing alternative to carbon steel. Stainless steel not only offers corrosion resistance but better fire resistance rating compared to unprotected carbon steel. However, there is a lack of design guidelines which are based on experimental and finite element analyses of stainless steel structures alone. Rather, current design guidelines for stainless steel structures are based on those available for cold-formed carbon steel, with some rules essentially identical. Cold-formed stainless steel exhibits a nonlinear stress strain behaviour and has a markedly lower proportionality stress and significant loss of material stiffness beyond this stress. Other material characteristics exhibited by stainless steel include different properties in tension and compression, anisotropy, and significant work hardening capability. Furthermore, each of these characteristics depends on the alloy and the history of cold-working and/or annealing. The influences of these material characteristics on the distortional buckling mode have not been substantiated in the carbon steel-based design guidelines.

Part of this research is to investigate the distortional buckling behaviour of simple lipped channel columns with and without intermediate stiffeners under axial compression load. Data from experimental and finite element analyses will be used to evaluate and to propose modifications to the current design guidelines for stainless steel available in Australian, North American and European codes. The data will also be used to develop direct strength design curves specific to stainless steel austenitic and ferritic alloys.

This research also involves the investigation of the local and distortional buckling mode of stainless steel roof sheeting. Again, current design codes for roof sheeting are based on carbon-steel codes and do not account for stainless steel material properties. As such, it is important to establish whether or not the current codes are safe. This research involved the design of a test rig which would allow bending moment to develop in the roof sheeting whilst minimizing the effects of shear and axial forces. This experimental research will lead to the development of a set of equations for the design of stainless steel roof sheeting.

• Lecce M, Rasmussen KJR, “Distortional Buckling of Cold-Formed Stainless Steel Sections: Experimental Investigation”, Journal of Structural Engineering, in press.
• Lecce M., Rasmussen KJR., “Distortional Buckling of Cold-Formed Stainless Steel Sections: Finite Element Modeling and Design”, Journal of Structural Engineering, in press.
• Lecce M, Rasmussen KJR., “Experimental Investigation of the Distortional Buckling of Stainless Steel Sections” Research Report 844, Department of Civil Engineering, University of Sydney, 2004.
• Lecce M, Rasmussen KJR., “Finite Element Modelling and Design of Stainless Steel Sections” Research Report 845, Department of Civil Engineering, University of Sydney, 2004.
• Lecce M., Rasmussen KJR., Experimental Investigation of Distortional Buckling of Cold-formed Stainless Sections, Proceedings of the 17th Specialty Conference on Cold-Formed Steel Structures, Orlando, Florida, 2004
• Lecce M; Rasmussen KJR., “Design of Stainless Steel Sections Against Distortional Buckling” , Proceedings of the 17th Specialty Conference on Cold-Formed Steel Structures, Orlando, Florida, 2004

Buckle formation

Roof sheeting