University of Sydney’s civil engineering researchers are set
to release a design process for steel structures in Australia that will guide
safe, reliable, and cost effective steel construction in one simple,
Structural reliability expert Dr Hao Zhang says that a team of
researches has completed a four-year project that analysed steel structures
used in the Australian construction industry, and following up with a reassessment
of Australia’s steel structural modes.
“In the project we shifted the focus of design from the
individual components and its connection strengths to the overall structural
behaviour and strength of the entire system,” says Dr Zhang, senior lecturer in
the School of Civil Engineering, and co-investigator on the project.
“The component-based design approach can overestimate the
load carrying capacity of structural systems, causing unsafe designs.”
The structural analysis process developed by the
University’s team combines examination, evaluation and capacity checking into a
single step. Their research of the past four years has also highlighted
failures within the system currently used.
“The core of this project has been a rigorous statistical
assessment of the system strength which considers structural redundancy,
consequences of failure and statistical variations in loading and variables
affecting the frame strength,” says Dr Zhang.
“The one-step process provides the opportunity to consider
the consequences of failure during the design phase of the process. This is
vital when designing any building including magnificent structures”
‘System reliability-based criteria’ is the name of the
guidelines the team created for designing steel structures, and it advocates the
guidelines to all those considering designing with the material.
“The aim is to make design-by-analysis the chosen method for
designing steel structures. Current procedures rely on hundreds of equations
stipulated in national codes for calculating the strength of individual
components of structural frames, like columns and beams. These procedures will
become obsolete when designing by analysis, as member strengths are implicitly
checked,” notes Professor Kim Rasmussen, head of the School of Civil
Professor Rasmussen also highlighted the researcher
innovations and says it is important to change the model of steel structural
“What is important is the strength and weight of materials
used to design reliable steel frames.”
“However, the veracity of the structural components and the
parts that connect them as a whole are the hidden key.”
He highlights the new one-step process as effective in
giving Australian businesses the competitive edge on the international market.
“The outcomes of this project will help Australian
structural design firms and engineers to be at the forefront of design
methodology. It also can assist Australian companies competing in South East
Asia, Middle East and European markets,” he says.
“We envisage that over time our one-step methodology will be
adopted throughout the world.”
The research team consisted of:
Professor Kim Rasmussen, University of Sydney
Dr Hao Zhang, University of Sydney
Five PhD students, University of Sydney
Professor Bruce Ellingwood, Georgia Institute of Technology, Atlanta
for more information.