PRESS RELEASE: A research project between COWI and Imperial College London has won a Research Award from the Institution of Structural Engineers.
At present, there is very limited research and testing of hollow steel pipe piles, commonly used in marine construction. The research indicates that they may be susceptible to inelastic buckling and low cycle fatigue when subjected to cyclic loading, such as during an earthquake. A reliable and predictable description of the inelastic post buckling behaviour of steel circular hollow sections in the marine pile range in cyclic loading would be indispensable for their performance based seismic design in the marine pile range - however, such a characteristic does not yet exist.
Thanks to a £6000 research award from the Institution of Structural Engineers, the research team are designing an experimental campaign to close the current knowledge gap.
COWI Technical Director, Dimitris Pachakis, with Senior Lecturers Adam Jan Sadowski and Christian Málaga Chuquitaype from Imperial College London, are experimentally and numerically exploring and the ductile behaviour of hollow steel sections in cyclical loading in the inelastic range.
The experimental part will test specimens with slenderness ratios similar to those of marine piles in cyclic bending, aiming to gain understanding on local buckling and low cycle fatigue.
The numerical part aims to model and predict the observed section behaviour with finite elements.
The study is expected to have a significant impact to the structural engineering industry. Not only will it stimulate further research into full scale testing under cyclic loading conditions, but any reliable results will also influence the upcoming update of the 'Standard for the Seismic Design of Piers and Wharves' (ASCE 61-19) of which COWI is a member. This Standard is the de-facto guideline used for seismic design of marine structures worldwide.
The six-month research campaign will begin on February 2019 and results will be disseminated following completion.