Engineering Department > Structures Group


Morley Symposium on Concrete Plasticity and its Application

  23rd July 2007

On 23rd July 2007 a Symposium was held at Emmanuel College Cambridge on the theme of Concrete Plasticity and its application. It was held to mark the retirement later this year of Chris Morley. The attendees at the symposium wished to acknowledge his tremendous contributions to the study of plasticity in concrete. The first major conference on the subject was held at the Technical University of Denmark in Lyngby, Copenhagen in 1979, under the auspices of IABSE and the chairmanship of Prof Bruno Thurlimann.  Since then, the principles of plasticity have been incorporated into the design procedures for most concrete structures, although the link is not always made explicit.  Virtually all designs for flexure, all code rules for shear, and all analyses of slabs, both for punching shear and bending, rely on the fact that the Safe Load Theorem applies to concrete structures.  Major problems are now being caused because the current generation of young engineers believe the results of their nonlinear finite element analyses.  It would be interesting to know whether any of them could actually quote the lower bound theorem; they would probably be horrified to compare the actual stresses in their structures with the values they have assumed.


Many of the paper will also appear in a special issue of the Magazine of Concrete Research, to be published early in 2008.

The organisers would like to thank Parsons Brinckerhoff, Atkins, The Happold Trust, Cobras, Trinity College, and Emmanuel College for contributing to the costs of holding the symposium and publishing the proceedings.

Copies of the proceedings can be purchased from Nami Norman <>, Dept of Engineering, University of Cambridge, price £10 including post and packing.



Paper Title

Chris Morley

University of Cambridge

When Plasticity?

Mik Braestrup


Yield Line Theory and Concrete Plasticity

Michael Collins, Evan Bentz, Edward Sherwood & Liping Xie

University of Toronto

An adequate theory for the shear strength of reinforced concrete structures

John Eyre

University College London

Geometric considerations of plasticity in structural concrete analysis and design

Ashraf Ashour & Keun-Hyeok Yang

University of Bradford

Application of plasticity theory to reinforced concrete deep beams

K Baskaran University of Moratuwa Irregular flat slabs designed according to structural membrane approach
Chris Burgoyne & Andy Smith University of Cambridge Automated Lower-bound analysis of slabs

Douglas Clyde

University of Western Australia

Affinity Properties of Truss Model Nodes

Steve Denton & Chris Morley

Parsons Brinckerhoff

Accounting for bi-axial bending in yield line analysis of reinforced concrete slabs

Tim Ibell & Steve Denton

University of Bath

Recent applications of plasticity theory to concrete shear problems

Colin Gurley TAFENSW Sydney Disproportionate collapse at lost corner columns
Jacques Heyman University of Cambridge Unreinforced Concrete Plasticity
Kamal Jaafar Balamand University Shear behavior of reinforced concrete beams with confinement near plastic hinges
Peter Lowe University of Sydney Where to from here?

Ian May

Heriot-Watt University

Why isn't the Morley sandwich approach to slab reinforcement used every time?

Cam Middleton

University of Cambridge

Generalised collapse analysis of concrete bridges

Ganga Prakhya

Sir Robert McAlpine

Plasticity applications in reinforced concrete and prestressed concrete structures

Wendel Sebastian

University of Bristol

Analysis of concrete structures across the ductility spectrum

Robin Spence

University of Cambridge

Earthquake loss estimation for reinforced concrete buildings: some problems