University of Plymouth

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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 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

Images:

• protect against flooding (Bangladesh/New Orleans) 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 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

• • • • 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.

http://www.millenniumassessment.org (2000)

• • • • • • •

Quantitative Life 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 algae which actively remove CO 2 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?

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