The Temple Mills Bridge in London was reconstructed from 2004-2006. The original 1963 bridge had deteriorated due to water ingress and reinforcement corrosion. The reconstruction involved demolishing the old bridge down to the existing foundations and riverbed, then constructing new piers, abutments, and a precast concrete deck. Environmental considerations like flood risk, habitat creation, and noise/pollution mitigation played a key role. Careful planning and risk management were needed due to the bridge's strategic location and need to maintain traffic flow during construction. The reconstruction secured this important transport link in advance of nearby Olympic development works.

1. School of
Engineering and Design
First International Conference on
Advances in Bridge Engineering
Bridges - Past,
Present and Future
co-sponsored by
“Celebrating the 200th Birth
Anniversary of Isambard
Kingdom Brunel”
www.brunel.ac.uk/about/acad/sed/bec2006
to be held at Brunel University, West London
26-28th June 2006

2. Proceedings of the First International Conference on Advances in Bridge Engineering 26 - 28 June 2006
TEMPLE MILLS BRIDGE RECONSTRUCTION
Temple Mills Bridge Reconstruction
Javad Akhtar
Hyder Consulting (UK) Ltd.
Abstract
Temple Mills Bridge built in 1963, carries the A106, over the River Lea in five spans.
The original bridge decks of 50m overall length, consist of precast, prestressed
concrete beams with in situ concrete infill, supported on piled reinforced concrete
piers and abutments. Extensive chloride contamination and difficult maintenance
issues led to the decision to replace the structure. A number of alternative deck
replacement solutions were examined – including complete “encapsulation” within
new precast concrete arches.
Careful risk management played an important part in being able to develop the most
economical solution within the framework of a design and build contract under NEC
Option C conditions of contract. Review of geotechnical data and concrete testing
concluded that the existing foundations were acceptable for re-use. The replacement
adopted a similar span arrangement, but with a deck of semi-integral construction,
bearings only being provided at the abutments. The original piers were demolished
down to river foundation level and new ones built up with epoxy coated reinforcement
below river level. The abutments were extended to form a series of plinths for the
bearing shelf with existing faces encased in a 100mm thick skin of new concrete. piers.
A wide range of Environmental mitigation measures were undertaken, including
hydraulic design to cater for future “Global Warming”. The design allows for the
passage of small mammals along the river-banks and bat roosting facilities. The
environmental management plan included a range of measures to mitigate noise and
pollution threats.
Keywords: Bridge Reconstruction, Rehabilitation, Concrete Repair, precast prestressed, foundations,
environmental, traffic management, GGBFS, PFA, DPS, epoxy coated reinforcement.

3. Proceedings of the First International Conference on Advances in Bridge Engineering 26 - 28 June 2006
TEMPLE MILLS BRIDGE RECONSTRUCTION
1.0 Background
Temple Mills Bridge is sited an Olympic champion’s stone’s throw from the site of the main Olympic Park
in Stratford. The bridge, built in 1963, carries one of the area’s major routes, the A106, over the River Lea.
The existing bridge consists of two nearly identical structures, 50 metres long, each carrying a three lane
carriageway, a footway/cycleway and a central paved verge. The bridge decks are separated by a 3.66 metre
gap and consist of precast, prestressed concrete beams with in situ concrete infill. Each five-span bridge
structure is supported on reinforced concrete piers and abutments supported on piles. Unusually, the piers are
articulated by means of bearings halfway up the pier, with a concrete ‘hinge’ detail at the top. Whilst many
parts of the structure were judged beyond economic repair, the river foundations and the abutment supports
were re-used.
Due to the high traffic volumes in the area, the replacement took place in two parts with traffic diverted
initially all to the south carriageway while demolition and reconstruction of the North Carriageway was
undertaken. By careful re-assessment of the existing deck four lanes were maintained for traffic, and services
diverted to the other side.
2.0 Defects in original structure
Most of the problems with the bridge stem from inadequate waterproofing at the time of construction. The
bridge was built just before the Highways Agency (HA) introduced specific requirements for waterproofing.
The bitumen impregnated jute used at the time has failed to prevent water ingress, to the point that stalactites
had formed on extensive areas at the underside of the bridge deck. The water ingress had also caused the
sliding bearings of the abutments to seize to a point where they were beyond repair.
Previous investigations had also revealed that reinforcement corrosion due to chloride attack in the insitu
concrete “stitch” over the piers had progressed to the point that the deck could no longer sustain the applied
hogging moment over the piers due to vehicle loading on the continuous deck.
Fortunately, the original contractor had designed beams to cater for simply supported loading conditions,
rather than attempt to refine the design to suit the actual complex continuous frame system. Thus, although
the bridge is currently not supporting the applied loading in the manner intended by the designer, the reserve
of strength in the beams has saved it from a more imminent demise.
A further concern with the structure was that a “mechanism” type failure mode of the piers was possible
due to the presence of bearings at the lower part of the piers and the loss of moment restraint due to corrosion
of reinforcement in the insitu concrete stitch at the top of the pier. This failure mode was only prevented by
the restraint provided by the abutment curtain wall and the seized abutment bearings. Furthermore parapets
did not conform to current standards.
These concerns over long-term structural behaviour and the whole life costs of a growing programme of
investigation, monitoring and repair led to Hackney Council’s decision to replace the structure.
3 Project/Risk Management
Hyder Consulting was appointed by the London Borough of Hackney in 2003 as Project Managers to
review and consolidate the findings of previous studies, to develop the options for the crossing and to
supervise the detailed bridge design and construction phases. In February 2004, contractor Norwest Holst
with Designers Mouchel Parkman started the £2 million, 18 month design and build project to replace the
existing bridge.

4. Proceedings of the First International Conference on Advances in Bridge Engineering 26 - 28 June 2006
TEMPLE MILLS BRIDGE RECONSTRUCTION
3.1 Pre-contract Planning
Prior to letting the design and construction contract, the following steps were undertaken:
• Scheme, program & procurement strategy review with LB Hackney
• Stakeholder Consultation
• Technical Investigations and Studies (Hydraulic Flow Modelling, Traffic Counts, Traffic Modelling,
Site Investigations, Planning Review, Environmental Appraisal, Contaminated Land investigation etc.
• Design performance criteria and specifications
• Preparation of reference designs
• Contract Documents
• CDM Risk Assessment and Pre-Tender Health & Safety Plan
These processes are illustrated on the figure 1.
3.2 Contract Strategy
The “ideal” form of construction contract was initially considered as NEC Form A for simplicity of
administration and price certainty. However this was changed to NEC Option C to meet LBH accelerated
program and to allow early letting of the design and construct contract prior to completion of the various
investigations and studies. Tender documents were issued Oct 03 (two months after Hyder appointment).
Tender evaluation was based on a 60:40 Quality: Price weighting.
3.3 Risk Management
The key risks identified at project planning stage are given in Table 1 below, with a brief indication of
mitigation measures. During construction a much more extensive Risk Register was developed based on
contractual “Early Warnings”.
Table 1 Perceived Risks and Proposed Mitigation Measures
Risk Comment/Mitigation
Travellers not moving Two separate Traveller Community encampments were present adjacent
to the site. Sensitive discussion and liaison resulted in peaceful
relocation of these communities.
Geotechnical - Lack of Information/ reuse of
existing foundations (abutment & river
piles/pedestals)
An extensive amount of Ground Investigation data was obtained from
Transport for London (TfL) archives relating to the A12 Project. Further
Site Investigations were instigated during the course of the contract.
Construction unknowns Dealt with through contractual “Early Warning” register.
Environment Agency (EA) requirements &
timing of responses
Maintained close contact with relevant responsible officers within EA.
Extensive hydraulic and environmental studies undertaken.
Potential Traffic Problems Traffic studies undertaken and flows modelled to prove feasibility.
Close liaison with Police, TfL, Buses and transport operators.
Public Objection Extensive consultations and publicity.
Identification of key stakeholders and planning to minimise impacts.
Control of Construction Costs and planning
of Funding
Administration of contract to limit instructed variations and close liaison
with funding authorities, including raising risk awareness and provision
of cash-flow forecasts.
Statutory Undertakers (SU’s) requirements
and information issue
Early development of plans with SU’s and close liaison.
Major Sewers (syphon+Chambers) under
bridge at river bed level
Close liaison with Thames Water Utilities. Provision of protective
measures.

5. Proceedings of the First International Conference on Advances in Bridge Engineering 26 - 28 June 2006
TEMPLE MILLS BRIDGE RECONSTRUCTION
4 Alternatives Considered
One of the options considered during project planning stage was the propping and encapsulation of the
existing structure on precast concrete arches launched from the existing river foundations. While this option
would have avoided demolition with the associated requirements for traffic and services diversions, it was
ruled out in conjunction with the Environment Agency because of worries over the hydraulic and ecological
effects on the River Lea. Indeed, environmental issues are to the forefront generally because of the bridge’s
location on the fringes of the Lea Valley Regional Park.
5 Environmental Considerations
One consequence is that the deck of the new bridge will be 0.5 metre higher than the original. This again
takes into account some Environment Agency (EA) concerns about a 1 in 100 year flood event with a further
20% allowance for “Global Warming”. Hydraulic studies were scoped and commissioned by Hyder from
external consultants – Halcrow, in order to re-assure the EA that the results were indeed independent from the
construction team.
The “hard” revetments adjacent to the riverbank have been lined with “Geoweb” plastic mesh infilled with
granular material in order to aid soil retention, vegetation growth and habitat creation. A minor surface bank
slip adjacent to the structure has been stabilised by willow stakes.
The design of the new structure will also allow for the easier passage of small mammals along the river-
banks and will provide for bat roosting facilities. The construction team liaised closely with Hackney Council
and the Environment Agency to mitigate potential noise and pollution threats.
5.1 Traffic Modelling
Due to the critical location of the structure, Hackney were anxious to ensure that traffic flows were catered
for with minimal disruption. Hyder therefore undertook advance traffic-modelling studies and developed an
outline Traffic Management Scheme in liaison with Hackney, Transport for London, emergency services,
transport operators and other stakeholders. The planned construction phasing allowed for services diversions,
with the new structure also providing spare capacity to cater for future services.
6 Aspects of Design of Replacement Structure
6.4 Structural Form and Deck
Refer to figures 6 and 7 for deck details (from drawings by Messrs Mouchel Parkman). An infilled precast
prestressed deck was adopted, continuous and integral over intermediate pier transoms, supported by
laminated rubber bearings at abutments. This semi-continuous form minimised any additional lateral loads
on the existing concrete bored piled abutments.
6.2 Materials
In order to improve longer term durability, the new bridge was constructed using a Ground Granulated
Blast Furnace Slag (GGBFS) concrete mix. This in turn was subject to a two part spray waterproofing.
To prevent environmental pollution of the watercourse, impregnation of the concrete was undertaken using
“Deep Penetrating Sealant” rather than Silane. This forms a permanent protective “glass” coating to the outer
pores of the concrete that does not require renewal. DPS whilst having a history of use in Norway and other
countries, does not previously appear to have been used in the UK.

6. Proceedings of the First International Conference on Advances in Bridge Engineering 26 - 28 June 2006
TEMPLE MILLS BRIDGE RECONSTRUCTION
6.3 Foundations
The existing 1.5m diameter, 6m deep cylindrical reinforced concrete “Pedestal” foundations were
geotechnically appraised for upper and lower bound geotechnical parameters and judged capable of taking the
loads from the new structure (which in any case were lower than pre-existing loads).
Contingency risk-management planning was undertaken in case the concrete condition (which would only
be apparent once the existing piers were damaged and cofferdams installed) was found to be poor. However
in the event the pedestals were found to be in good condition.
Whilst the effects of the enlarged tops of concrete pedestals have been hydraulically modelled and shown to
have little impact on the flow of the River Lea, large pieces of concrete from the deck demolition will be
placed around the pile cap to mitigate the possibility of scour on the pile caps below the water level. This is
being done as a precaution against possible eddy currents under and around the lips of the enlarged pedestals.
Refer to figure 5 New Piers Founded on Existing "Pedestal" Foundations.
7 Construction
Demolition of the original bridge started with the northern carriageway. This initially required the
stabilisation of the existing bridge piers and the positioning of pontoons underneath the bridge deck.
Hydraulic breakers then moved in to break up the deck, with the debris being scooped up from the pontoons
below using small robotic excavators refer to figure 8 Deck Demolition on Pontoons.
As the deck is removed temporary struts were put up to support the piers before removal of these down to
river floor level. This was undertaken in two stages, firstly down to the level of the pier bearings, followed by
removal of the stubs below the waterline down to the level of the top of the “Pedestal” foundations.
In order to begin the construction of the new piers, precast concrete rings were first embedded around the
existing pile caps. As well as creating enlarged pedestals, these served as coffer-dams during the river level
works and provided shuttering moulds for the concrete pour of the new piers. Prior to the pour, new epoxy
coated reinforcement bars were drilled and resin anchored in to the existing pedestal.
While tests on the loading capabilities of the abutments showed good performance with core test results of
60 KPa, there was evidence of some corrosion of non-structural steel reinforcement in the abutment face due
to water leaking in from the top and side of the expansion joints. Mouchel-Parkman, who carried out the
detailed design for Norwest Holst, proposed that, the top of the existing abutments be scabbled down and new
reinforcement bars resin anchored in at close centres. The abutments were then extended to form a series of
plinths for the bearing shelf with existing faces encased in a 100mm thick skin of new concrete.
The buried faces of the abutments were tested and found to have negligible chloride contamination,
however due to the uneven concrete finish it was decided to extend the “encapsulation” concrete skin to the
rear face of the abutment also.
In the river itself, particular care was required working around the three 1 metre diameter sewage pipes
which run longitudinally through the middle of the bridge just below the river floor. In the first stage the
pontoons protected these pipes. However it was found that the pontoons grounded easily and would actually
obstruct the river in the event of an unforeseen flood event. For demolition of the southern half of the deck
the pontoons were omitted and a crash-deck provided - comprising a 300 mm thick granular pad over two
layers of steel sheet piles laid flat on the bed (spanning the pipes).

7. Proceedings of the First International Conference on Advances in Bridge Engineering 26 - 28 June 2006
TEMPLE MILLS BRIDGE RECONSTRUCTION
Precast beam erection was undertaken using a mobile crane sited just behind the abutments (refer to figure
9). Difficulties were encountered at the junction between previously erected North Deck and the South deck
due to the need to “mesh” into the 3 dimensional reinforcement cage provided out of the cross-head and
continuity reinforcement from the pre-erected deck. These were overcome by use of reinforcement couplers.
8 Conclusion
Completion of this bridge in March 2006 secured this important local transport link and marks the first
project to cross the finish line at the start of the major developments on the adjacent Olympic site.
Acknowledgements
The author, whose role was as Project Manager, wishes to acknowledge the assistance and support of….
Client Manager Joe Figurado London Borough of Hackney
Supervisor Richard Williams Hyder Consulting (UK) Ltd.
Contractor Mark McGleenon Norwest Holst Construction Ltd
Contractor’s Designer Andrew Foster Mouchel-Parkman Ltd
Figure 1 Pre-Construction Contract Project Management Processes
Figure 2 Existing Bridge

8. Proceedings of the First International Conference on Advances in Bridge Engineering 26 - 28 June 2006
TEMPLE MILLS BRIDGE RECONSTRUCTION
Figure 3 Installation of Phase 1 Traffic Management

9. Proceedings of the First International Conference on Advances in Bridge Engineering 26 - 28 June 2006
TEMPLE MILLS BRIDGE RECONSTRUCTION
Figure 4 Scheme Options Considered
Figure 5 New Piers Founded on Existing "Pedestal" Foundations
(Note details slightly modified during construction)
Figure 6 Deck Cross-section at Central Reserve

10. Proceedings of the First International Conference on Advances in Bridge Engineering 26 - 28 June 2006
TEMPLE MILLS BRIDGE RECONSTRUCTION
Figure 7 Deck Long-section at Abutment and Abutment “Encapsulation” Detail
Figure 8 Deck Long-section at Abutment and Abutment “Encapsulation” Detail
Figure 8 Deck Demolition

11. Proceedings of the First International Conference on Advances in Bridge Engineering 26 - 28 June 2006
TEMPLE MILLS BRIDGE RECONSTRUCTION
Figure 9 Precast Beam Erection

12. Call for papers
The theme of the conference will be ‘Bridges - past,
present and future’. Papers can be presented on
any aspect of the development of knowledge,
techniques, innovations, control, monitoring and
management processes which may represent an
advancement in the field of bridge engineering. A
special session on Historical Bridges, with particular
emphasis on Brunel’s work, is planned to celebrate his
200th birth anniversary.
Invited Speakers
The following have indicated acceptance of
invitations to make Keynote Presentations:
Mr Steven Brindle
English Heritage, UK
Prof Jean Armand Calgaro
ENPC and GCPC, Paris, France
Prof Jacques Heyman
Cambridge University, UK
Mr Makoto Kitagawa
Honshu Bridge Authority, Japan
Mr Brian Pritchard
Consultant, formerly Atkins, UK
Prof Santiago Huerta
University of Madrid, Spain
Prof Michael Collins
Toronto University, Canada
Requirements and dates
Authors wishing to present a paper should submit an
abstract (300 words approx.). Abstracts and Papers
must be in English and should clearly indicate the
contact author details (affiliation, address, telephone,
FAX and e-mail). The abstracts may be submitted by
post (Bridge Conference 2006, Research Office,
School of Engineering and Design, Brunel University,
Uxbridge, UB8 3PH, UK) or e-mail
(bridgeconf.2006@brunel.ac.uk)
Target dates
Submission of Abstracts 30 December 2005
Acceptance of Abstracts 6 January 2006
Submission of full Manuscripts 28 February 2006
Final acceptance will be based on peer-review of the
full manuscript.
Final Manuscripts should be no more than
8 pages in length and must comply with the
'Instructions for Preparing a Paper' available at
www.brunel.ac.uk/about/acad/sed/bec2006
Manuscripts should be submitted via e-mail or
the electronic submission form at the conference
website. In exceptional circumstances, full
manuscripts may be submitted for consideration as
paper hard copy. In all circumstances, a paper hard
copy and an electronic CD-ROM version of the final
manuscript of the paper must be provided for the
publication process by the due date.
First International Conference on
Advances in Bridge Engineering
www.brunel.ac.uk/about/
acad/sed/bec2006
Isambard Kingdom Brunel was a visionary and amongst the most influential engineers of the last millennium.
His wide-ranging works, his aesthetic sense and legacy have withstood the test of time and have been a
constant inspiration to generations of engineers. He was a tunnelling engineer, a railway engineer, a
transportation engineer, a buildings engineer, a marine engineer but above all he was a bridge engineer. Even
the general public who have no special knowledge of engineering matters tend to automatically warm to the
inherent beauty and merit of his works and contribution, recognising the genius he was. The splendid Clifton
Suspension Bridge of his design is an example of this artistry. The University is proud to be named after this
great engineer and following his footsteps shall endeavour to advance the frontiers of knowledge and
engineering for the future.

13. Exhibition
There will be an associated exhibition of selected
equipment, instrumentation, software and
information relating to bridge engineering, providing
delegates an opportunity for exchange of ideas and
information on topics of current interest in the field.
Organisations interested in exhibiting their products
or services should contact the Conference
Administrator for terms and conditions.
Venue
Howell Theatre, Brunel University, Uxbridge,
Middlesex UB8 3PH.
Booking Conditions
i) Early booking is recommended; places will be
reserved on first come first served basis.
ii) Reserved places can be reassigned to another
person by prior written request.
v) Delegates are encouraged to travel by public
transport. A limited number of car parking permits
will be available for parking at the University.
vi)All rights reserved with the University.
Application Form:
First International Conference on Advances in Bridge Engineering on 26-28 June 2006
For reserving a place, please either register online at www.brunel.ac.uk/about/acad/sed/bec2006 or complete this
application form with Conference fee (cheque or transfers made payable to Brunel University) or address for
invoicing to:
Mrs Carole Carr [e-mail: bridgeconf.2006@brunel.ac.uk]
Research Office Manager
Bridge Engineering Centre
School of Engineering and Design
Brunel University
Uxbridge
Middlesex UB8 3PH Tel: 01895 266 962 Fax: 01895 269 797
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Registration Fee
The registration fees for the various categories of participants at the conference, which include a copy of the
proceedings, a reception, buffet lunches and refreshments for the 3 days of the conference, are as follows:
Fee received: Before 1 March 2006 From 1 March 2006
Delegates £495 €740 £545 €815
Authors £445 €665 N/A
Students (proof required) £295 €440 £325 €485
Day rate delegates/authors £245 €365 £275 €410

14. SCHOOL OF ENGINEERING AND DESIGN
102240 0106
Conference Organising Committee
Prof Arvind Kumar Kumar Associates & Brunel University
Mr Chris Brown Brunel University
Prof Luiz Wrobel Brunel University
Conference Administrator
Mrs Carole Carr Brunel University
Conference Advisory Committee
Prof Ben Barr Cardiff University & Institution of Civil Engineers
Mr Robert Benaim Robert Benaim & Associates, UK
Mr Steven Brindle English Heritage, UK
Prof Jean Armand Calgaro ENPC and GCPC, Paris, France
Mr Michael Chubb Atkins, UK
Prof Michael Collins Toronto University, Canada
Mr Patrick Dallard Arup, UK
Dr Stuart Davis Mott MacDonald, UK
Prof Christopher Earls Pittsburgh University, USA
Mr Ian Firth Flint & Neil Partnership, UK
Prof Bill Harvey Bill Harvey Associates, UK
Prof Paulo Helene Sao Paulo University, Brazil
Prof Jacques Heyman Cambridge University, UK
Mr Makoto Kitagawa Honshu Bridge Authority, Japan
Prof Paulo Laurenco Minho University, Portugal
Mr Angus Low Arup, UK
Prof Jianming Lu Research Institute of Highways, China
Prof Claudio Modena Padua University, Italy
Mr Graham Nicholson Tony Gee & Partners, UK
Mr Brian Pritchard Consultant formerly Atkins, UK
Mr Nigel Ricketts Network Rail, UK
Prof Charles Roeder Washington University, USA
Mr Benjamin Sadka Highways Agency, UK
Prof Berthold Schlecht Technical University Dresden, Germany
Prof Fernando Stucchi Sao Paulo University, Brazil
Mr Keith Wilson Faber Maunsell, UK
Dr Richard Woodward Transport Research Laboratory, UK
Surname
First Names
Organisation
Position
Address
City
Post Code
Tel
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Date
Fee cheque enclosed
£Or Invoicing Address (UK only)
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