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The Response of Steel Structures
to Fire and Earthquake
Structural Performance
in Fire
Extreme earthquakes and fires cause steel structures to yield
beyond their design capacity, exposing structural weakness and
revealing collapse mechanisms. Performance based structural and
fire design significantly enhance a steel structure’s capacity
to resist the effects of fire and earthquake.
Research made in New Zealand into the performance based design
of steel structures to resist earthquakes has transferred readily
to the performance based design of steel structures to resist
fire. The resulting significant advantages relating to improved
design efficiency and economy have been incorporated into Holmes
design standards in New Zealand, allowing a more thorough and
in depth assessment of the impact of extreme fire events on the
inelastic response and collapse of steel structures.
Performance Based Fire Engineering Experts
In regard to all aspects of steel structures in fire, our team
of more than 20 professional fire engineers is lead by:
Martin Feeney (MFireE, M.IPENZ, MSFPE) has 19 years
experience in structural engineering and 8 years fire engineering
experience. He spent 2 years on secondment to the Heavy Engineering
Research Association, carrying out research and developing design
methods for steel structure response to earthquakes and fire.
He is author and co-author of a number of articles and publications
on performance based design of steel structures exposed to fire,
including a major design guide on Seismic design of Steel Structures.
In consulting practice he specializes in the design of steel structure
response to fire. These methods have been applied to a wide range
of commercial projects in New Zealand and Australia.
Linus Lim (MFireE, PhD) is a recent postgraduate in
fire engineering from the University of Canterbury, New Zealand.
His particular field of expertise is in behavior of steel and
concrete structures in fire conditions and in non-linear finite
element analysis of structures in fire. His research has focused
primarily on structural analysis and design for fire conditions,
using the non-linear finite element program, SAFIR, developed
specifically for this purpose. This was supplemented by full scale
experimental fire tests.
Fire Scenarios
| Limit State Design
Our design approach considers a full range of natural fire scenarios
as well as the code specified ASTM furnace test fire curves. The
natural fire curves, as defined by post flashover fire models
given in the Euro codes and recognized publications such as the
Australian Fire Engineering Guidelines, are derived from the likely
fire load and ventilation characteristics of the particular firecell
and building under consideration.
The structure’s response to the effects of exposure to these
temperature time histories is evaluated to determine the extent
of fire protection needed to keep the strength and deformation
of structural members within accepted limits. Similarly, the structure’s
response to the effects of fire without any form of protection
can also be modeled.
Progressive Collapse in Fire
Analysis of collapse mechanisms is frequently used to determine
weaknesses in the seismic resistance of structures. The capacity
design approach used in New Zealand, for both steel and concrete
structures, is fundamentally based on understanding collapse mechanisms.
Holmes Group has developed in-house software specifically for
time history structural analysis, to determine the consequence
of time dependent structural degradation on collapse mechanisms.
Performance Based Design Environment Case Studies
The performance based Building Codes used in New Zealand and Australia
allows the application of first principles design to projects
on a regular basis. Consideration of post flashover fire behavior
and the analysis of its influence on steel structures are a regular
part of our design process.
Our clients benefit from this structural and fire design expertise
with successful results on a range of new and existing projects
in New Zealand and Australia - including high rise office towers,
apartment buildings and stadium complexes.
For further information, please see www.holmesfire.com |
