Structural Engineering
Our long history of research in structural engineering includes some of the first experimental investigations into structural buckling behaviour and optimisation of beam cross sections early in the nineteenth century. The group has current expertise in most areas of structural engineering, and the main fields of ongoing research activity are as follows.
Stability and Buckling
The long-standing interest involving both theoretical and experimental investigations has continued with emphasis on the interpretation of new phenomena and the development of practical design and analysis methods for the buckling of thin-walled structures such as shells, box girders, subsea pipelines, spacedomes and steel-framed structures. Of particular current interest is the nature of the imperfection-sensitive post-buckling behaviour of constrained elements such as pipelines, road pavements and railtrack (upheaval buckling) and linings to thick-walled shell structures and subterranean cavities.
Assessment of Damaged Structures
The prediction
of distortional damage and imperfections, due to impacts and collisions
in thin metal shells used in the offshore oil industry and in vehicles,
has been developed using simple elastic-plastic models. Their extension
to post-damage response has allowed identification of both the residual
strength and fatigue implications of this damage. This work extends
a long-standing interest in the effects of imperfections on the
strength of shell structures.
Pioneering work has now been published by the group on the assessment
of the strength of flexural reinforced concrete elements subject
to reinforcement corrosion. This is part of a broader programme
also considering the strength of damaged reinforced concrete columns.
Reinforced Concrete Structures
In addition to the integrity assessment studies referred to above, our work on the plastic analysis of slabs with compressive membrane action has led to a straightforward method of estimating load capacities in practice. Its use depends on an understanding of the behaviour of slab areas surrounding a failure mechanism. Our current work is an investigation of such areas of slab in multi-bay building and bridge deck slabs and in ground bearing floor slabs.
Dynamics
The group
is active in the development of MEMS-based transducers to allow
routine monitoring of the dynamic behaviour of civil engineering
systems. These new transducers are light, cheap and wireless, and
conjure up the possibility of routine health monitoring of structures.
Work is also underway to refine methods for identification of structural
system properties from transducer readings. A popular example is
to use measurements of mode shapes and natural frequencies to calibrate
a finite element model of a structure.
Durability and Repair of Structures
The group’s work is principally focused on the problem of reinforcement corrosion in concrete structures. Investigations, both theoretical and experimental, on various methods of rehabilitating concrete structures including electrochemical chloride removal and bonded fibre composite sheets are currently being conducted. A novel approach to designing reinforced concrete structures with enhanced durability is being developed. The latter extends a long-term interest in the relationship between cracks, cover and reinforcement corrosion and the adequacy of existing code provisions for minimising such problems in future construction.
Deployable Structures
The need to
package large aerospace structures into the confines of a rocket
launcher and then to deploy them in orbit, has led to the development
of new concepts for reflector antennas. Ongoing research has shown
that the trade off between the low mass of thin film reflectors
versus the high surface accuracy of solid surface reflectors can
be solved by flexible thin shell reflectors with tuneable stiffness.
The capability of passively varying the stiffness of a structure
in its different states (packaged or deployed) is an extremely useful
feature and is beneficial to many other fields. One further field
of interest is in the application of deployable structure technology
and passive stiffness control on implantable biomedical devices.
The academic staff of the group are:
Senior Lecturer
Chanakya Arya BSc PhD DIC CEng MICE
Professor of Civil Engineering
James Croll BE,PhD,CEng,CMath,FREng,FICE,FIStructE,FIMA,FRSA
Lecturer in Structural Dynamics
Philippe Duffour PhD, Meng General Engineering
Head of Design Group
John Eyre BA, BSc, PhD, RIBA
Senior Lecturer
Deputy Dean of Students (Welfare)
Paul Greening BEng, PhD
Rodolfo Lorenzo
Royal Academy of Engineering Visiting Professor in Teaching
Ed Mccann
Reader in Earthquake Engineering
Tiziana Rossetto MEng MSc PhD DIC
Senior Research Associate
John Twigg
Visiting Professor
Perry Vassie BSc PhD M.Math
