Transcript Slide 1

The Potential of
Composite Materials in
Civil Engineering applications
John Summerscales
University of Plymouth
Civil engineering
• ICE definition includes …
– about creating, improving and protecting
the environment in which we live.
– facilities for day-to-day life and for transport
and industry to go about its work.
– Civil engineers design and build bridges,
roads, railways and tunnels. They also design
and build tall buildings and large structures …
Outline of talk
• Buildings, highways, water supply and
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drainage, coastal protection etc
Numerical modelling (FEA/CFD) and
optimal design (e.g. genetic algorithms)
Standards
Quality, Environmental, Safety and Health
(QuEnSH) systems
Challenges
Key characteristics of composites
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low density
high specific modulus/strength
creep and fatigue resistance*
durability in corrosive environments*
ballistic resistance
Lin Liao et al, Journal of Advanced Materials, 1998, 30(4), 3-40.
* G Pritchard, Reinforced Plastics Durability, Woodhead, 1999.
*
New materials
• fibres:
– basalt
– reclaimed “milled” short carbon fibres
– natural fibres
• matrix:
– bio-based resin systems
• nano-additives
• embedded sensors and biomimetics
Re-bar
• potential use for pultruded sections
• pulsed microwave curing giving alternating
– cured solid section
– uncured flexible sections
Cladding
• Mondial House
– one half of panels removed after 33 years service
– one half of panels cleaned and polished.
• American Express, Brighton c.1977.
– structural cladding supporting glazing.
• functional formwork?
Images:
Reinforced Plastics, May 2007, 51(5), 26-29+31-33.
Reinforced Plastics, September 2006, 50(8), 22-32.
Housing
Experience of
(a) prefabricated housing
+ (b) naval vessels
= (c) floating, or submerged, residences to
• alleviate pressure on fertile land
• protect against flooding (Bangladesh/New Orleans)
Images:
FRP bungalow built by Charles Roberts (WY), circa 1963 (photo by JS, 2004).
HMS Wilton FRP hull built by Vosper Thornycroft circa 1970.
Housing 10 billion people
• Build
– high … multi-storey building
• energy required to lift components
– dry … into the desert regions
• bonded composites require no water
– wet … onto or under the sea
• (as on earlier slide)
Floating infrastructures
• VISIONS Network of Excellence
– Visionary Concepts for Ships & Floating Structures
– European FP6 priority 1.6.2 sustainable transport
– http://www.maritime-visions.net
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free-ports
renewable energy
NIMBY: not in my back yard
offshore gambling casinos
Image from:
WEGEMT Academic Contest Guidelines 2009.doc
Third world
.. and .. disaster relief
• move the village to the water
or pipe the water to the village ?
• lightweight water tankers
– more water, less vehicle
• prefabricated shelters
(p)rehabilitation
• Earthquake containment
– over-wrapped bridge supports
– why not adopt “functional formwork”
rather than do this retrospectively?
• Pipework
– in-situ-form pipe lining
• Historic structures
– Ightham Mote (National Trust)
Bridges
• Several modest examples in Europe
• Some strengthening/rehab in USA
• proposed Straits of Gibraltar Bridge
as a flagship project
U Meier, Proposal for a carbon fibre reinforced composite bridge across the Strait of
Gibraltar at its narrowest site,
Proceedings of the Institution of Mechanical Engineers,
Part B: Management and Engineering Manufacture, 1987, 201(B2), 73-78
Transport
Need for private cars
or effective public transport ?:
• dedicated elevated/tunnelled routes
 ensuring no delays
 regular and reliable service
 on-demand provision?
High speed rail-links
• Shanghai airport to centre
– 30 km in 7min 20s (advertised as 8min)
– maximum normal speed of 431 km/h (268 mph)
– … but mostly ac-/de-celerating
• flight check-in is tedious, so
• given concern over aircraft emissions
the challenge is to convert domestic air
(intra-continental) to high speed rail.
Coastal defences
• University of Liverpool Department of Mathematical Science
– metamaterial “invisibility cloak”
could reduce the risk of large water waves
overtopping coastal defences
– need to replicate in a ‘real’ life situation
to protect land from natural disasters/tsunamis, and
defend structures such as oil rigs in the ocean.
M Farhat, S Enoch, S Guenneau and AB Movchan
Broadband Cylindrical Acoustic Cloak for Linear
Surface Waves in a Fluid. Physical Review Letters,
26 September 2008, 101, 134501:1-4.
Renewable energy
• Land
– hydroelectric
– wind
– geothermal
• Sea
– waves
– tidal barrage and tidal stream
– ocean thermal energy conversion (OTEC)
Numerical modelling
and optimal design
• Finite Element Analysis
– laminate stacking sequence
– material/structural anisotropy
• Computational Fluid Dynamics
• Genetic Algorithms
– but where is the underlying database?
Standards
• Positive:
– Sims (NPL) drove aerospace CRAG
to ISO standards
• Negative:
– lack of standards for thick composites
– difficulty of addressing multiple laminate
configurations/stacking sequences
– need a champion for this sector
Joints and connections
• adhesives
• pultrusions with connectors:
– Composolite®
– Startlink
Quality, Environmental, Safety
and Health (QuEnSH) systems
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Quality > ISO 9000 series
Environment > ISO 14000 series
Safety and Health > OHSAS 18000 series
QuEnSH aims to integrate these systems
Quality, Environmental, Safety
and Health (QuEnSH) systems
• Off-site preparation of modular systems
• Lower embodied energy
• More comprehensive
(quantitative) Life Cycle Assessment
• Embedded systems for
structural health monitoring
Cost
• Composites inherently expensive?
• Move fabrication to low-wage economy
• Consider system costs, e.g.
– Autovia del Cantabrico
first carbon-fibre composite bridge in Spain
– easy and quick to assemble
– completed in 10 hours using a 50 tonne crane
(equivalent structure in concrete > 400 tonne crane)
Entering the ecological age
Peter Head’s
Brunel International Lecture series for the
Institution of Civil Engineers
“Entering the ecological age: the engineer's role”
http://www.ice.org.uk/brunel
heavy focus on biomimetics
Environment
Sustainability Assessment to
Overcome Barriers to Renewable Construction Materials
• NetComposites and BRE lead LINK collaborative research project
funded through the renewable materials programme.
• Focus on assessing the environmental credentials of
naturally derived construction materials.
• Raw material supply – including crop production and land-use
• Energy requirements for primary and secondary processing
• Durability of these naturally derived materials
compared to conventional alternatives
• End of life issues
including recovery/re-use, recycling, composting and disposal.
Robert Constanza et al
• The value of the world’s ecosystem
services and natural capital
[Nature, May 1997].
• The biosphere provides us with services
worth some US$33 trillion per year
- nearly double the world’s GDP!
Millennium Ecosystem Assessment
• Easy to express in monetary terms:
– Agriculture and livestock, hunting, fishing, water
supply, genetic resources, various chemicals
• More complex to evaluate (regulatory services):
– Carbon sequestration, atmospheric regulation, air
quality, water supply, erosion, nutrient supply,
regulation of pests and diseases
• Difficult to evaluate (cultural services):
– Aesthetic, artistic, educational, spiritual/religious,
recreation and leisure.
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http://www.millenniumassessment.org (2000)
Quantitative
Life Cycle Assessment (QLCA)
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acidification
climate (global warming)
eutrophication
ozone
resource depletion
smog
toxicity
ISO14040 series
Yves Sciama:
• … in 2007 global warming managed to
impose itself as a world-wide issue
- whereas biodiversity is still struggling to
rise above the status of a marginal issue.
[research*EU 56 dated June 2008].
A world without bees
• strange case of vanishing western honeybee
– colony collapse disorder
• varroa mites and/or agrochemicals
– dangerously out of kilter with nature?
– the world can't survive without it:
• “no more pollination, no more plants, no more man”.
• May Berenbaum:
– “managed honey bees will cease to exist by 2035”
Alison Benjamin and Brian McCallum, A World Without Bees
Guardian Newspapers, June 2008. ISBN-13: 978-0852650929.
MR Berenbaum, Colony Collapse Disorder and Pollinator Decline,
US House of Representatives Committee, 29 March 2007
Algae
• as the ocean warms,
the area that can support growth of algae
grows smaller … driven ever closer to poles,
until algal growth ceases.
Threshold for failure of the algae
which actively remove CO2 from the air
is ~ 500 parts per million (ppm)
which we will reach ... in about forty years.
James Lovelock, The Revenge of Gaia
Allen Lane, London, 2006.
ISBN-13: 978-0-713-99914-3
Social factors
• Skilled industry personnel
– accredited training
– higher salaries in aerospace/Formula 1?
• Educate the users
– Plymouth Civil Engineering BEng students
take same 20 credit composites course as
BEng Mechanical Engineering with Composites
Key challenges
• conservatism of civil engineering industry
• price sensitivity
• absence of comprehensive
“materials” property database
• absence of design codes
• automated manufacture
Acknowledgements
• Toby Mottram, University of Warwick
• Dave Easterbrook, University of Plymouth
• Fethi Azizi, University of Plymouth
download the PowerPoint from
www.tech.plym.ac.uk/sme/composites/cobrae.ppt
 Thank you for your attention
… any questions?