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Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
The Evolution of
Advanced Polymer Composites
in the
Civil Infrastructure
Professor Len HollawayDepartment of Civil Engineering
University of Surrey
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
•In the civil infrastructure the interest in compositescommenced during the second world war with the introduction of radomes.
•Between 1940 and the late 1960s composites had rathera chequered career with one-off fun systems being made.
•By the late 1960s and into the 1970s composites werebeing taken more seriously by the industry and systemsinvolving load bearing and infill units were being produced. These were used in conjunction with skeletal frameworks made from steel or reinforced concrete.
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
In 1974 the first all composite GFRP structure using the
building block method was a classroom structure
conceived and erected by Lancaster County Council.
The classroom system was made by hand lay-up using:
•Intumescent resins in the laminate external surface.
•An integral skin phenolic foam on the inside surface.
•CSM glass/polyester composite system.
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
GFRP Composite Class Room System 1974 conceived by Lancashire C.C.
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
In the mid 1980s and into the 1990s the development of the first automated building block was undertaken byMaunsell Structural Plastics.
Using this system the following All Polymer Composite
structures were manufactured: 1. Aberfeldy Bridge
2. Bonds Mill Bridge
3. Two storey building – used as offices at the 2nd Seven Crossing.
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Maunsell Plank and Box Beam Cross-section
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Aberfeldy Footbridge Bridge
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Opening ceremony of the Bonds Mill Lift-bridge Gloucestershire
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Composite Bridge Decks
To replace conventional degraded deck systems in minimum time the development of durable lightweight easy installation systems have been produced in advanced composites.
The system may be used in two forms:
•Replacement for existing but deteriorated decks
•Used as new structural components on conventional or new supporting structural elements
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
An all composite bridge deck being developed by a European consortium (ASSET) - Section of ASSET deck unit (By kind permission of Mouchel Consultants)
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Wickwire Run Bridge - Taylor County, West Virginia, USA (By kind permission of Creative Pultrusions Inc Alum Bank, PA.)
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Upgrading and retrofitting of structures and structural units.
Structures may require to be strengthened for a number of reasons.
•Design deficiencies
•Inferior materials
•Poor construction, workmanship/management
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
There is a choice between strengthening [or demolition]
Flexural strengthening •Bonding a plate onto the soffit of the beam
•Wrapping with a carbon fibre pultruded plate of prepreg wrap.
Shear strengthening
•Bonding a plate onto the vertical sides
•Wrapping prepreg around the sides and soffits and if possible around the whole beam
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Thin layer of separated concrete
Exposed plate endInternal steel rebars
Typical mode of plate separation for a shear span/beam depth ratio of 4.0
CFRP Plate
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Prestressed carbon fibre/epoxy plate bonded to soffit of cast iron beam (By kind permission of Mouchel Consulting)
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
General view of Hythe Bridge (By kind permission of Mouchel Consulting)
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
(a) (b) (c)
Various systems for wrapping FRP composite on to the sides of a Tee RC beam.
(a) FRP wrapped entirely around the beam.
(b) FRP wrap in the form of a U (either with or without pin fixings depending upon bond requirements).
(c) FRP wrap bonded to the two sides of the beam.
Pins
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
FRP jacket -fibre in horizontaldirection.
Reinforced concretecolumn
Main direction of fibres (in thehoop direction)
Wrapping of prepreg composite around concrete column
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Systems that combine advanced polymer composites with conventional materials, in particular, concrete.
The objective is to use the two materials to their best advantage. For instance:-
•Concrete is poor in tension
•Advanced polymer composite have high tensile strengths
•Concrete has a high compressive strength value
•Advanced Polymer composites have low compressive reactions because of buckling of the unit, (assuming unit is a thin plate).
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
GFRP
CFRP
Concrete
GFRP Permanent shuttering
Hybrid GFRP/CFRP/concrete rectangularBeam (after Meier & Trantafillou)
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
CONCRETE
Two plies of +/- 45o GFRP manufactured from XLTM65U prepreg
4mm plywood plate
Eight plies of 0/90o CFRP from XLTM65U prepreg
30
31.08
1.08
3.44
116.02151.08
140
80
: Cross-section of Tee beam of composite/concrete construction
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
•Concrete core prevents buckling of the hollow FRP tube.
•FRP tube confines the concrete and increases strength and ductility.
•The best characteristics of the individual materials are utilised. The system was developed for two reasons
1. To produce non-corrosive columns and piles.
2. To enhance the ductility of the system.
Concrete filled filament wound composite tubes
The advantages of these systems are :-
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Section of Carbon fibre shell girder showing girder to deck connection (By kind permission of V. Karbhari and F Seible)
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Kings Stormwater Channel Bridge Salton Sea, California, USA (By kind permission of V. Karbhari and Seible UCSD)
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
I-5/Gilman advanced technology bridge to link separate areas of the Campus at University of California, San Diego, USA
(By kind permission of V. Karbhari and F. Seible UCSD)
Advanced Polymer Composites in the Civil Infrastructure
Structural Composites Research Unit, Department of Civil Engineering - Univ. of Surrey
Challenges of FRP material in the construction industry
•FRP materials have been successfully implemented into infrastructure projects – but their long-term durability (50+ years) required to be investigated.•Substantial amounts of useful information do existbut it is scattered and not easily accessible.•Effects of sustained stress need to be considered.
•Effects of environment on ambient cure systemsneed to be considered.