Advanced Polymer Composites

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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 Hollaway

Department 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 composites

commenced during the second world war with the

introduction of radomes.


Between 1940 and the late 1960s composites had rather

a chequered career with one
-
off fun systems being made.



By the late 1960s and into the 1970s composites were

being taken more seriously by the industry and systems

involving 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 by

Maunsell 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 2
nd

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 end
Internal 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

horizontal

direction.

Reinforced concrete

column

Main direction

of fibres (in the

hoop 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 rectangular


Beam

(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 +/
-

45
o

GFRP
manufactured from
XLTM65U prepreg


4mm plywood
plate


Eight plies of 0/90
o

CFRP from
XLTM65U
prepreg



30


31.08


1.08


3.44


116.02


151.08


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 exist

but

it is scattered and not easily accessible
.


Effects of sustained stress need to be considered.


Effects of environment on ambient cure systems

need to be considered.

Advanced Polymer Composites in the Civil Infrastructure

Structural Composites Research Unit, Department of Civil Engineering
-

Univ. of Surrey

The end of


the


History Lesson