Current research activity
- High strength steel structures
Experimental and FE research of the structural response of high strength steel (S460 – S690) stub columns, beams, slender columns and beam-columns. Assessment of design rules in EN 1993-1-1 and EN 1993-1-12. Utilization of post-tensioning to mitigate excessive deflections. Optimization of post-tensioned high strength steel trusses
- Stainless steel structures
Effect of material nonlinear response on the ultimate response and ductility of stainless steel cross-sections, members and indeterminate structures. Assessment of novel laser welding fabrication on the structural response of welded stainless steel cross-sections members.
- Interfacial strength of concrete filled steel tubular columns
Composite action between concrete and still in concrete filled columns relies on the achievement of perfect bond between steel and concrete, therefore assessing the interfacial strength at the steel concrete interface is of paramount importance. To this end experimental and analytical research has been conducted in collaboration with Tianjin University in China to identify the various mechanisms and quantifying their contribution to the interfacial strength between concrete and steel.
- Deformation based design metallic structures
Stainless steel and structural steel structures exhibit significant strain-hardening in the post elastic material range, which is customarily not accounted for in design, thereby not harnessing the materials full structural potential. To this end the Continuous Strength Method has been developed by Prof. Leroy Gardner, which is in essence a deformation based design procedure that allows for strain hardening exhibited by stocky cross-sections. Current research in this area includes the derivation of design rules for non-doubly symmetric stainless steel sections in bending, the derivation of design rules to treat cross-sections under combined loading and extending the method to elevated temperatures, i.e. design cross-sections exposed to fire conditions.
- FRP-strengthened concrete beams
Most structural strengthening techniques for reinforced concrete beams in shear utilise FRP sheets which are connected to the concrete member by means of an adhesive layer. In most cases, failure occurs due to delamination/deboning of the sheet in the resin rich concrete face and is mainly defined by the tensile strength of the underlying concrete, thus not allowing the full potential of the FRP sheets to be exploited. To address this issue a novel anchoring scheme has been developed by the research team of Professor Manos at the Aristotle University of Thessaloniki and research is underway to optimize the scheme at local and structural level.
- Plastic design of stainless steel continuous beams
Eurocode design provisions specify a slenderness limit for plastic stainless steel sections but do not allow plastic design, mainly due to lack of available test data. Given the high material ductility of stainless steel and its high initial material cost, the extension of plastic design procedures to stainless steel indeterminate structures is warranted. To this end experimental and numerical research is being conducted and initial results are encouraging.
- Structural response of Elliptical Hollow Sections
Elliptical Hollow Sections (EHS) and Oval Hollow Sections (OHS) are a recent addition to the tubular section family and combine the structural efficiency associated with sections with different stiffness about the principal axes with the aesthetics of Circular Hollow Sections (CHS). Due to their unique geometry and in particular the fact that they are not comprised of plated elements nor have they a constant curvature, their treatment at cross-sectional level is challenging. The structural response of stainless steel OHS in compression and bending has been studied both experimentally and numerically. Suitable slenderness parameters have been identified and the suitability of the Eurocode 3 design rules to this form of sections has been verified, whilst a safe buckling curve, different form the ones specified in EN 1993-1-4 has been proposed. Further research concerns their structural response under combined loads at ambient and elevated temperatures.
- Stability of sandwich structures
Analytical and numerical research into the buckling and post-buckling response of sandwich compression members employing stiff face plates and flexible cores. Effect of assumed beam theory and pre-existing damage.