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The Potential of Composite Materials in
Civil Engineering applications
John SummerscalesUniversity 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
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
• 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
• 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 carsor 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 situationto protect land from natural disasters/tsunamis, and defend structures such as oil rigs in the ocean.
M Farhat, S Enoch, S Guenneau and AB MovchanBroadband 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
• 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 Cantabricofirst 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 agePeter 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
Sustainability Assessment to Overcome Barriers to Renewable Construction Materials
• NetComposites and BRE lead LINK collaborative research projectfunded 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.
Environment
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.• http://www.millenniumassessment.org (2000)
QuantitativeLife Cycle Assessment (QLCA)• 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 algaewhich actively remove CO2 from the airis ~ 500 parts per million (ppm)which we will reach ... in about forty years.James Lovelock, The Revenge of GaiaAllen 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 asBEng 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 fromwww.tech.plym.ac.uk/sme/composites/cobra
e.ppt
Thank you for your attention
… any questions?