Tension structures discussed in this research monograph cover pre-stressed cable nets, girders, trusses, and fabric membranes.
Tension structures discussed in this research monograph cover pre-stressed cable nets, girders, trusses, and fabric membranes. Attention is also drawn to cables in suspension bridges – a special form of a cable truss.
In their tensioned state, cables and fabrics adopt unique geometric con?gurations, which cannot be described by simple mathematical functions. Instead, they have to be found through iterative computations supported by physical experiments – a process known as ‘form-?nding’. Form- ?nding is a theme running through almost all chapters of the book, highlighting conceptual design issues and advocating the use of principles observed in nature when seeking to achieve optimal structural forms, or ‘minimal’ structures.
The form-?nding methodology is extended to suspension bridge cables, to emphasise the fact that they are not structures of ‘known shape’.
The second edition covers the most commonly used computational methods used in modelling tension structures, but also contains a signi?cant amount of new material,
wide coverage of tension structures projects, focusing on iconic designs around the world
a more detailed description of architectural fabrics,with reference to the CEN/TC 250 European Code of Practice
stronger justi?cation for using the concept of the soap-?lm analogy in form-?nding of fabric membranes, based on the results of the latest research and recommendations of the European Design Guide for Tensile Surface Structures
Derivation of a new ‘shape’ equation for the case of an elastic (extensible) suspension bridge cable under the deck weight and cable weight – it is shown how this equation reduces to an equation describing a catenary form (in the case of cable weight only) and a parabolic form (in the case of deck weight only)
a brand new section on the relevance of the shape equation for inextensible cables to the form-?nding of rigid structural forms, such as arches. The focus here is on the inverted shape of a constant stress cable and how it relates to the design of the iconic Gateway Arch in St Louis, MO, USA
a comprehensive and insightful coverage of patterning methods for fabric structures (i.e. 3D to 2D transformations required to manufacture the fabric membrane), presenting the latest non-standard computational approaches.
The aim of the book is to enhance understanding of tension structures from both practical and theoretical points of view and to provide insights into problems associated with the computational modelling of their structural form and behaviour.
About the author
1.1.De?nitions and classi?cations
1.2.Strength and stiffness of architectural fabrics
1.3.Types of architectural fabrics
1.4.Boundary tensioned membranes
1.6.Pre-stressed cable nets and beams
1.7.Design process of tension membranes
1.8.Main features of tension membranes
1.9.Conventional roo?ng forms versus tension membranes
1.10.Closing remarks 20
2.1.General concepts. Nature’s ‘secrets’
2.2.Concept of a ‘minimal surface’: historical background
03 Geometrically nonlinear behaviour: solutions using commonly used numerical methods
3.2.Commonly used computational methods for the analysis of geometrically nonlinear behaviour
3.3.Transient stiffness method
3.4.Force density method (original formulation)
3.5.Dynamic relaxation method
3.6.Computational static analysis versus form-?nding
04 Dynamic relaxation method
4.1.Dynamic relaxation method with viscous damping
4.2.Dynamic relaxation method with kinetic damping
4.3.Application of dynamic relaxation to cable networks
4.4.Evaluation of the dynamic relaxation method
05 Cable roof structures. Case studies
06 Tension cables in suspension bridges.A case of form-?nding
6.1.‘Shape’ equation for an inextensible suspension cable
6.2.‘Shape’ equation for an extensible suspension cable
6.3.Numerical modelling of shape of suspension bridge cables
6.4.Form-?nding of suspension bridge cables:practical aspects
6.5.Form-?nding, or form-dictating?
6.6.Relevance of ‘shape’ equations to form-?nding of arch structures
07 Modelling of tension membranes
7.3.Surface discretisation for use with thetransient stiffness method:limitations of the approach
7.4.Surface discretisations used with the dynamic relaxation method
7.5.Line elements in modelling of stable minimal surface membranes
7.6.Application of triangular elements to modelling of stable minimal surface membranes
7.7.Mesh control – implications for design
7.8.Patterning of membranes
7.9.Numerical accuracy and criteria used for convergence
Appendix I Architectural fabrics
Appendix II Cables for tension structures
Appendix III Minimal surfaces
Appendix IV Viscous damping in dynamic relaxation
Appendix V Finite-difference analysis of inextensible cable Load case 1:deck weight only