Technologies, Repair Solutions, Management Strategies and Materials for Concrete Infrastructure
Submitting Institution
Sheffield Hallam UniversityUnit of Assessment
Electrical and Electronic Engineering, Metallurgy and MaterialsSummary Impact Type
TechnologicalResearch Subject Area(s)
Chemical Sciences: Analytical Chemistry
Engineering: Civil Engineering, Materials Engineering
Summary of the impact
Over a period of 20 years, Professor Mangat and colleagues in the
Materials and Engineering
Research Institute's (MERI's) Centre for Infrastructure Management have
developed significant
expertise of concrete materials and structures related to deterioration,
repair and maintenance of
infrastructure. This body of research has led to professional practice
and economic impacts
related to repair selection, asset management systems, curing systems and
novel repair/building
materials. Mangat's expertise in concrete deterioration, its remediation
and repair has been
developed into commercial software systems for bridge and asset management
and the national,
professionally accredited training course for bridge inspectors/engineers.
In the REF impact period,
bridge management software has been adopted by over 30 UK local
authorities and training
delivered to 392 bridge management professionals. Commercialisation of two
of Mangat's research
innovations, alkali activated materials (AAMs) and low voltage accelerated
curing systems
(LOVACS), has achieved direct sales of £0.5m and development of the
spin-out Liquid Granite Ltd.
Additionally, his corrosion protection systems have been adopted by
engineering consultants Mott
MacDonald, enabling them to win commissioned corrosion-remediation
works of over £1m
Underpinning research
Mangat joined SHU in 1993 (from University of Aberdeen) as Professor. He
has been submitted by
SHU for the last three RAEs and is submitted to REF2014 as Category A. In
1993 he brought with
him an EC-funded project [i] on expert systems for performance assessment
and optimum
inspection and maintenance strategies for concrete structures. This was
subsequently advanced at
SHU by research into the long term performance of concrete repair in
highway structures [ii]. The
key research developments from this work were: models for long-term
deterioration processes in
reinforced concrete, particularly chloride diffusion and reinforcement
corrosion [1]; equations for
the prediction of long-term residual strength and stiffness of corroding
members [2]; and methods
for characterising the interaction between repair patches and substrate
concrete in terms of
material properties and repair methods [3].
Mangat's research on deterioration remediation of concrete subsequently
diversified into
corrosion protection (CP) systems, which he developed with Dr Paul
Lambert, Technical Director of
Mott MacDonald and, since 2005, Visiting Professor at SHU. Collaborative
research between
Mangat and Lambert, supported by a Royal Society Industrial Fellowship to
Lambert [iii], initially
concentrated on numerical modelling of CP systems and their experimental
verification. This led to
development of optimum CP system designs for corroding reinforced concrete
and steel framed
masonry structures [4].
Having established expertise in concrete deterioration and repair, Mangat
was well placed to
identify the limitations of concrete repair materials and the inefficiency
of site curing methods with
respect to the durability of repair. This triggered the research that led
to his development of alkali
activated materials (AAMs) and low voltage accelerated curing system
(LOVACS).
Research on AAMs, was conducted between 1995 and 2004, supported by EU
funding [iv].
Initial research identified the principle of using inorganic alkali
material to activate waste-derived
reactive powders, thereby avoiding use of high CO2-producing
hydraulic cement. Subsequent
experimental investigations determined chemically optimised compositions
of multiple reactive
powders, filler and activator [5], so characterising the key parameters
governing properties such as
strength and durability. Further work developed admixtures capable of
giving control over AAM
setting time and shrinkage, thereby addressing practical considerations
such as placement,
compaction, on-site curing and long term durability. Formulations suitable
for different repair
methods were then developed through an EU Regional Development Scheme
grant. Subsequent
industrially-sponsored research [v] determined methodologies by which to
exploit the excellent
adhesive properties of AAMs to achieve dual function anode systems which
offer both CP and
structural strengthening to concrete structures. AAMs proved to be fire
resistant at temperatures
exceeding 1100°C, significantly out-performing cement-based or
polymer-modified materials. The
former typically explode when heated towards 400°C. As described in section
4, research
publications on AAMs were restricted in order to protect IP related to
this finding.
LOVACS, a novel conductive polymer technology, comprises a flexible
polymer-coated
textile membrane which, when appropriately incorporated, provides
accelerated and efficient curing
to in-situ repairs and to concrete construction in general, especially in
cold weather. LOVACS was
initiated through a Teaching Company Scheme (TCS) awarded to Inditherm
Plc and Mangat's
group at SHU in 2003, subsequent work being supported by EPSRC [vi] and EU
grants [vii]. The
research that underpins LOVACS started with the development of basic
relationships between the
composition/thickness of the conductive polymer coating, the size and
spacing between electric
rails and the optimum size of the polymeric heating element. Subsequently,
relationships between
power input, the arrangement of the polymeric heating elements (in
parallel, series, with or without
common middle rail), and the heat output were determined, leading to
optimisation of curing
system designs for a range of specifications. For example, generic
relationships were derived by
determining the performance of polymer blankets with different power
ratings and configurations on
the curing efficiency of concrete elements and repair patches. From these,
it proved possible to
optimise the LOVACS curing parameters (power, temperature, time) for
production of a range of
durable cured materials and components. On the basis of this discovery, an
international patent [6]
was granted in 2005 to Mangat and Catley (the TCS associate) who went on
to achieve a PhD
(2009). Mangat's research activity in this field continues through an EU
grant to improve the quality
of concrete repairs using a novel accelerated microwave curing system
[viii].
References to the research
[1] Mangat, P.S., and Limbachiya, M.C., "Repair material properties for
effective structural
application" Cement and Concrete Research 27, 601 (1997)
DOI: 10.1016/S0008-8846(97)00027-6 13 Citations (WoS Sept 2013)
[2] Mangat, P.S., and Elgarf, M.S., "Bond characteristics of corroding
reinforcement in concrete
beams" Materials and Structures 32, 89 (1999)
DOI: 10.1007/BF02479434 36 Citations (WoS Sept 2013)
KEY REFERENCE
[3] Mangat, P.S., and O'Flaherty, F. J., "Influence of Elastic Modulus on
Stress Redistribution and
Cracking in Repair Patches" Cement and Concrete Research 30,
125 (2000)
DOI: 10.1016/S0008-8846(99)00217-3 25 Citations (WoS Sept 2013)
KEY REFERENCE
[4] Lambert, P., Mangat, P.S., O'Flaherty, F.J. and Wu, Y.Y., "Cathodic
Protection of Steel
Framed Masonry Structures — Experimental and Numerical Studies", Materials
and Structures
41, 301 (2008)
DOI: 10.1617/s11527-007-9240-2 1 Citation (WoS Sept 2013)
KEY REFERENCE
[5] Mangat, P.S., Khatib, J.M., and Wright, L., "Optimum utilisation of
FGD waste in blended
binders" Proceedings of the Institution of Civil Engineers,
Construction Materials 159, 119,
(2006)
DOI: 10.1680/coma.2006.159.3.119 1 Citation (Google Scholar Sept 2013)
[6] Mangat, P.S., and Catley, D.G., International Patent Application
"Heating Surfaces" Patent No.
WO/2005/036930. www.google.co.uk/patents/WO2005036930A1?cl=en
[i] EC Brite Euram grant BREU P3091, PI Mangat "Assessment of Performance
and Optimum
strategies for the Inspection and maintenance of Concrete Structures using
Reliability based
Expert Systems" (1992-95)
[ii] Department of Transport grant, LINK Programme, Contract TIO-49, PI
Mangat "Long term
performance of Concrete Repair in Highway Structures" £221,860 (1993-97)
[iii] Royal Society Industrial Fellowship to Lambert "Novel
Electrochemical Solutions for corroding
Steel Framed Masonry Heritage Structures" £93,000 (2001-05)
[iv] EU Copernicus programme grants CIPA CT94-0178, PI Mangat "Recycling
Fly Ash for
Producing Building and Construction Materials Based on a new Mineral
Binder system"
€87,500 (1995-97). and IC15-CT96-0741, PI Mangat "High Performance
Materials Derived
from Industrial Waste Gypsum" €54,010 (1997-99)
[v] C-Probe Ltd, PI Mangat "Dual Function, corrosion protection and
structural strengthening, CP
system for reinforced concrete" £27,112 (2010-13)
[vi] EPSRC, contribution from SHU CTA grant to studentship supervised by
Mangat, £75,178
(2005-07)
[vii] EU grant COOP-CT05-016374, PI Mangat "Development of Low Voltage
Accelerated Curing
Systems for Concrete" €856,046 (2005-07)
[viii] EU grant 605664, PI Mangat "MCure" £347,603 (2013-15)
[ix] Department of the Environment grant, LINK IST-033 DPU 96/64/84, PI
Mangat "An Expert
System for Optimal Repair in Reinforced Concrete Highway Bridges" £341,623
(1998-2001)
[x] Teaching Company Scheme 3739, PI Mangat "Prototype of Bridge
Management software"
£68,120 (2001-04)
Details of the impact
Mangat's impacts can be characterised as: influencing professional
practice, through software
and training; economic impact, through licencing of innovative
construction materials and a curing
method; and economic impact through enhancements to a provider's
capability.
Influencing professional practice, through software and training
Software: By the culmination of the project [ii] described in section
2, the LINK consortium and its
steering group had identified the need for bridge management software
including the optimum
repair capability for bridge managers. The software house, Research
Engineers Ltd, was therefore
inducted into the consortium and, in 1998, a further LINK project was
initiated [ix] to develop an
expert system for optimal repair in reinforced concrete highway bridges.
This fed into the
development of the commercial bridge management software via a TCS [x]. Infrastructure
Asset
Management (IAM) Ltd [A,B] was established in 2004 to commercialise
the resultant software,
under licence to SHU. The software implements the models and equations
from Mangat's research
(e.g. refs [1-3]) and uses these, alongside relevant asset design and
construction parameters, to
determine optimum maintenance, inspection and repair cycles [B]. IAM
has now become a leading
provider of infrastructure asset management software and consultancy. Its
Bridge Management
Xpert (BMX) system is the market standard for bridge management in
the UK, with a client base
including over 30 local authorities. The more recent Asset Management
Xpert (AMX) system
supports the management of any type of asset. The company has achieved
sales of ~£300k in the
REF impact period, with ongoing sales of ~ £100k pa.
Training: Mangat's expertise of repair, maintenance and management
of bridges has also been
intrinsic to the development of a professionally accredited course for
training bridge
inspectors/engineers to achieve the enhanced competences required by the
UK Bridges Board [C].
In 2012, the Department of Transport (DoT) adopted this Bridge Inspection
Competence and
Training Scheme for the training of all present and future bridge
inspectors in the UK [D]. Mangat's
contribution was fundamental to the development of this training scheme.
Its content was first
considered in 2008 when, on the basis of his research record, he was
commissioned by the Scots
Bridges Group to develop a training course on bridge management and
inspection [D]. This was
delivered to 85 bridge professionals in Dundee in 2008. Further iterations
of the training were
subsequently delivered in other locations (London, Birmingham, Dundee,
Glasgow, Sheffield,
Durham), 11 deliveries yielding a total attendance of 392 bridge
inspection and bridge
management professionals from local authorities, national authorities
(e.g. the Forth Bridge
authority), and private sector consultant engineers.
In the light of his lead in the area, Mangat was the only academic
consulted when, in 2008-9,
the UK Bridges Board undertook a review of bridge inspection competence
and training (see
section 9.1 of [E]). The recommendations of this review led directly to
the DoT Training Scheme.
Mangat and his colleagues (O'Flaherty and Lambert) are registered training
providers and
assessors [F]. O'Flaherty has been submitted to REF in UoA16. This
training, together with the
software and service impact described above, provide uniformity of bridge
condition assessment
across the UK, leading to efficient targeted investment by Government and
national asset
management agencies (e.g., National Rail).
Economic impact through licencing of innovative construction
materials and methods
The materials systems and curing approaches developed by Mangat to
overcome limitations of
conventional repair have also achieved impact. AAMs have been successfully
licenced to two
companies, Liquid Granite Ltd and C-Probe Systems Ltd,
whilst LOVACS, developed in
collaboration with Inditherm Plc, has been employed in a number of
constructions, such as the
Heathrow Terminal 5 Car Park.
AAMs: The Research and Innovation Office (RIO) at SHU worked
closely with Mangat to manage
and commercialise the IP in AAMs. This led to a decision to exploit AAMs
through a spin out
company, Liquid Granite Ltd [G], rather than publish detailed
research findings in the open
literature. Publication would have risked disclosing the optimum
compositions needed for
commercialisation — policing of IP within the construction industry is
impractical. Technology
transfer officers in RIO handled all negotiations in the establishment of
Liquid Granite Ltd, drafting
licence agreements and providing authorisation for signature. Market
analysis performed by RIO
also highlighted the future potential of AAM technology. Ongoing usage of
Portland cement is not
sustainable due to the volume of CO2 produced in its
manufacture, so the construction industry is
increasingly employing low carbon products such as AAMs.
Liquid Granite Ltd [G] was launched in 2006 (licence arrangements
agreed 2007) to exploit
AAMs. In this case SHU opted to take a licence agreement rather than an
equity stake. Equity is
held by a business angel plus two commercial partners, Church Holdings
Ltd and North Barnsley
Partnership who have collectively invested over ~£50k in cash and at
least an equivalent in-kind
contribution. Liquid Granite concentrates on fire retarding
applications, selling AAM-based precast
lintels meeting the highest fire resistance specification for fire plug
applications in buildings - total
sales in the REF period are £109k (licence income £5,455), including a
batch of AAM lintels
installed in 2012 Olympic village.
In 2012, C-Probe Ltd [H] took up a licence from SHU for a
customised version of AAMs,
concentrating on repair and corrosion protection of reinforced concrete
structures. This is based on
the electrically conducting version of AAMs and targeted at CP
applications [4], consistent with C-Probe's
other activities in the corrosion protection business and the
supply/installation of CP
systems. The customised version of AAM was trialled at Leeds Civic Hall
(limestone clad steel
framed building), pending a contract exceeding £100k.
LOVACS: The largest order achieved to date for LOVACS was by Laing
O'Rourke to cure
concrete during the Heathrow Terminal 5 construction. To July 2013, Inditherm,
had achieved total
sales of £262,165 [J], of which £35k (licence income £853) fell in the REF
impact window. Impetus
for further impact was provided by a 2013 research grant to Mangat, within
an EU consortium [viii].
Economic impact through enhancements to a provider's capability
Lambert's collaboration with the research of Mangat and O'Flaherty has
improved the international
competitiveness of Mott MacDonald (Lambert's employer). The
underpinning research on CP
systems has made Mott MacDonald a leading international provider
of durability enhancement and
corrosion remediation solutions to the built infrastructure sector [K].
Examples include advances in
the design of CP systems which have been implemented in consultancy
projects and the
development of a new dual function anode system for CP [L]. Commercial
projects resulting from
this within the REF impact window include: 85 Fleet Street, London — CP to
limestone clad steel
framed building, 2008 (value £800k); St James Buildings, Manchester — CP
to limestone and
glazed brick clad steel framed building, 2008 (value £100k); 992 Walnut
Street, Kansas City, USA —
Carbon fibre/AAM, CP design for granite clad steel framed portal, 2013
(value $80k); Severn
Bridge main suspension cables — residual life assessment (fees £50k);
Civic Hall, Leeds, trial
carbon fibre/AAM, CP installation to limestone clad steel framed building,
2013 (potential value
>£100k); Battersea Power Station — CP design optimisation (prospective
fees £20k).
Because these works focus on extending service life and avoiding
demolition/reconstruction,
each represents an overall cost saving of tens of millions of pounds to
clients and wider society.
Sources to corroborate the impact
[A] http://www.iamtech.co.uk
[B] Managing Director of IAM Ltd, corroborating source 1
[C] http://www.ukroadsliaisongroup.org/en/UKRLG-and-boards/uk-bridges-board/bridge-
inspector-training.cfm
[D] Group Chairman, Scots Bridges Group, corroborating source 2
[E] Page 108 plus further mentions in UK Bridges Board, Final Report
http://www.bridgeforum.org/bof/projects/bict/Bridge%20Inspector%20Training%20and%20Co
mpetence%20Phase%201%20Report%20Final.pdf
[F] http://www.shu.ac.uk/research/meri/bridge-inspection-competence-and-training-phase-2
[G] www.liquidgranite.co.uk
[H] Managing Director of C-Probe Ltd, corroborating source 3
[J] Managing Director of Inditherm Plc, corroborating source 4
[K] http://www.buildings.mottmac.com/materialsandcorrosion/
[L] Managing Director — Western Division, Mott MacDonald,
corroborating source 5