Issue 8 - February 2017
The Structural Concrete Alliance has announced the dates and locations for its free to attend Continuing Professional Development (CPD) seminars and Demonstration Days during 2017.
Designed to provide delegates with an introduction to Structural Asset Protection and Repair, the half-day CPD seminars offer an introduction to corrosion as well as techniques for repair, protection and strengthening.
Following the success of its first Practical Demonstration Day, held in September 2016, the Alliance is planning two such events during 2017. These free CPD events run from 9-3pm and offer delegates an opportunity to witness interactive demonstrations of key repair, protection, strengthening and sprayed concrete techniques.
Four CPD seminars and two Demonstration Days are scheduled during 2017:
For those unable to make the seminars or Demonstration Days, the Alliance also offers CPD presentations which can be delivered on-site to interested parties.
CCL provided a design and operational solution to replace the restrainment system on a reinforced concrete bund wall at a storage tank upgrade project for National Grid at Isle of Grain.
The liquid gas storage tank has a capacity of 50,000m3 and is surrounded by a 19.5m high bund wall, constructed using 470mm thick reinforced concrete, with 14 pre-loaded multi-wire bands in horizontal rebates providing restrainment.
In order to refurbish the bund wall, CCL devised a system for the safe de-tensioning of the existing bands, followed by installation of a bespoke solution involving specially designed and manufactured anchors, capable of restraining bursting forces of 223 tonnes per anchor. After the loaded tendons had been safely de-tensioned, scaffolding was erected around the circumference of the structure to allow the CCL team to remove the wires and prepare the concrete surface so that a new restrainment system could be installed.
Unbonded strands in special sleeves were individually placed in each recess of the bund wall, with an additional three bands installed in the lower section. The specially designed anchors were installed on each band of strands, which were then stressed to allow concentrated forces to be resisted for the full height of the bund wall.
Upon completion of 5,575 tonne of restrainment stress, a weatherproof coating was applied. All works were carried out while the tank remained operational, although at a reduced capacity.
The company was commended by the client for its innovative design and safe manner of working in an extraordinary environment.
The Resapol Training Academy was once again the venue for a full day of intensive training, with Fosroc’s Nick Smith and Jon Sweeney conducting in depth presentations and live demonstrations on their concrete repair products.
In line with its policy of continuous training and development for staff, Resapol regularly holds training exercises, seminars and live demonstrations for its sales staff. These sessions work to improve technical understanding of specific product lines, allowing its sales advisors to offer the best technical assistance when advising on the ideal material to use on specific projects.
The latest presentations and live demonstrations covered the full range of Fosroc concrete repair products, all of which conform to the requirements of BS EN 1504.
The training day consisted of looking into the physical properties of concrete and why it needs repair and protection; the typical causes of corrosion; and how to best understand and subsequently select the correct material for the job.
Resapol has eight depots with highly trained and experienced staff situated throughout the UK; in Leigh, London, Stockton, Kent, Southampton, Leeds, Bristol and Glasgow. Our depots work closely together controlling and sharing stocks to ensure sites nationally can be serviced with ease and speed.
Call 0800 083 1942 for more information regarding Resapol’s pricing and delivery options, or for more details on its training academy.
Sika has added two innovative new products to its superb repair mortar range that will enable large-scale infrastructure refurbishment projects to be completed more quickly, simply and cost-effectively.
Suitable for use in horizontal or vertical repairs, Sika® MonoTop®-614F is a high-quality, fast-setting pourable grout; an ideal rapid-apply solution for a wide range of large-scale repair projects such as bridges, marine structures, tunnels and buildings. Generally compliant with Highways England (Agency) standards, this proven repair mortar contains shrinkage compensators and high range water-reducing agents, meeting the requirements of Class R4 of BS EN 1504-3.
Sika® MonoTop®-614F, a polymer-modified, one component solution, is capable of repair depths up to 150mm in one application, making it a practical and cost-effective alternative to hand-applied mortars.
For high-profile infrastructure repair projects involving bridges, overhead soffits and bridge decks where minimising down-time is a key requirement, SikaCem®-133GP Gunite, a cement-based, polymer-modified sprayable grout, offers the perfect solution. This incredibly effective and easy-to-apply repair mortar is particularly suitable for use on road or rail projects where strict deadlines and penalties for over-running works programmes apply.
SikaCem®-133GP Gunite is generally compliant with Highways England (Agency) standards and meets Class R4 of BS EN 1504-3 requirements.
These latest additions to Sika’s wide-ranging and proven repair mortar offering are further evidence of the company employing the most advanced technologies, service and unique expertise for the benefit of customers and the construction industry.
Vector Corrosion Technologies Limited (VCTL), a long-time supplier of Galvashield® embedded galvanic anodes and Ebonex® conductive ceramic anodes for historic steel frame buildings is pleased to announce that it is expanding its range of solutions for impressed current cathodic protection (ICCP).
VCTL is proud to announce that the company has entered an authorised distributor relationship with De Nora Spa to promote its well-known Lida® range of catalysed mixed metal oxide titanium anodes. The product line includes Lida® Mesh ribbon anodes, Lida® Grid mesh anodes and Stargard™ discrete mesh anodes. The products will be conveniently stocked at VCTL’s location in the West Midlands to service European market needs.
Additionally, Vector has entered an agreement to represent the original conductive coating system, DAC-Anode from Corrosion Service in Canada. DAC-Anode is a non-destructive surface-applied ICCP system that has a successful 30-plus year history of providing cathodic protection for multi-storey carparks, flat balconies and similar structures. The system consists of a primary current distribution wire, the DAC-Anode WB single component anode coating, and a DAC-Anode Overcoat, an optional acrylic finish for improved aesthetics.
USL provided a waterproofing solution to the new Brunel Building carpark which was handed over to North Bristol NHS Trust by developers Carillion. The car park, located within the Brunel building extension, has more than 600 spaces for patients and visitors on site.
With key medical facilities below the first floor level, a combination of Blueshield PmB waterproofing by Pitchmastic PmB and Zoontjens paving provided superior structural waterproofing, insulated and then protected by Zoontjens trafficable Pardak parking system.
The Blueshield PmB system, which utilises over 40 years of tried and tested Pitchmastic PmB technology, outperforms many systems, as well as providing a market leading single point responsibility guarantee. The rapid installation and instant cure of Blueshield PmB provides the perfect surface to install the Pardak parking system.
One of a number of successful projects completed by USL StructureCare and Zoontjens, the solution offers long term value for money and superior protection to clients’ assets.
North Bristol NHS Trust Project Manager Martin Warren stated: "We are pleased to have opened our new car park to patients and visitors and hope it will improve their experience when coming to the hospital.”
Fosroc products were chosen for repairs to the abutments of the Eastern Road water bridge, which forms part of a new coastal defence scheme along the north of Portsea Island and is a major route into Portsmouth. The abutments, which had suffered erosion due to the coastal environment, required re-facing to ensure the bridge remained structurally sound.
A dry spray repair mortar was required for this project due to the large area of embankment that needed to be repaired and protected. Fosroc’s Renderoc DSR was chosen for the tidal areas due to its fast curing properties, early strength gain and low rebound. In other areas where fast curing was not so crucial, Renderoc DS was used.
Both materials are applied by dry spray methods and are specially designed for large repair areas and for enlarging or strengthening existing retaining walls or tunnel structures. They also meet the requirements of the Highways Agency Specification and EN1504.
Members of Fosroc's technical, operations, supply chain and customer services teams worked closely together to ensure that the contractor had material readily available and delivered exactly when required. The rapid setting time of Renderoc DSR and the fact that there is very little rebound resulted in improved productivity, reduced wastage and no contamination of the coastal water.
Gunform International Contracts Manager commented: "The material performed excellently and produced a first class job. We would certainly have no hesitation in using the products again and in recommending them to Clients in the future".
CRL Surveys have opened their sixth office in the UK as the business continues to expand to meet a growing demand for their services. The new office is in Kenilworth, Warwickshire, serving the Midlands Region, with five other offices in London, Bristol, Chesterfield, Runcorn and Falkirk.
The business has been established for over 20 years and employs 20 engineers and technicians, providing building and structure inspections to determine the nature and extent of any deterioration using the latest techniques.
CRL Surveys provides a comprehensive service using NDT equipment, intrusive sampling and testing, and visual inspections. Material samples are tested off-site for chemical analysis and compressive strength. The Inspection Reports include suitable repair options and can also include budget costs for the repair work to be undertaken.
The company works in all market sectors both in the UK and overseas for owners, contractors, surveyors and engineers. The staff are qualified in confined space working and working at height to ensure all work is executed in a safe and controlled manner.
The business is UKAS-accredited for on-site inspection services which provides assurance to clients that the work is undertaken to a recognised standard. The company is also proceeding with applications for the Bridge Inspection Certificate Scheme to ensure their staff meet the national requirements for bridge inspectors.
As part of the strategy to develop the business’s civil engineering capabilities in the highways and rail infrastructure sectors, structural strengthening specialist VolkerLaser has appointed Jeff Booth to the role of Technical and Development Director.
Jeff’s expertise lies in early contractor involvement; identifying and providing innovative solutions to complex structural problems during the development stages of a project.
An experienced construction professional, Jeff’s specialisms include temporary works design, hydraulic heavy lifting and sliding, bridge jacking and launching, bearing replacement schemes, structural strengthening and post-tensioning.
Jeff’s portfolio boasts high profile projects such as the replacement of bridge bearings on the Hammersmith Flyover, the refurbishment of Gatwick and Stansted Airport’s rail transit system, and the structural strengthening of the Brentford to Chiswick M4 elevated section.
Welcoming the appointment, Mike Weaver, managing director of VolkerLaser said:
“Jeff’s international experience and vast technical knowledge will provide new opportunities for our business to develop.”
Jeff looks forward to expanding the entrepreneurial business into new markets across the UK and internationally.
Corrosion Control Services Limited has undertaken repairs to the existing cathodic protection monitoring system installed on M275 Tipner Interchange Bridge in Portsmouth.
The contract, awarded by Colas, was to carry out initial testing of the system to confirm compliance with the standards. CCSL undertook testing with a portable power supply and showed that the ICCP system polarised and satisfied the performance monitoring criteria.
CCSL engaged the services of Omniflex to design and manufacture the new remote monitoring equipment.
The solution provided, uses the Omniflex innovative web-based “PowerView ICCP System” and incorporates their highly efficient Powerterm T/R’s for reduced carbon footprint. It can be operated and controlled by the client locally on an Easyview Touchscreen Interface or remotely via the web.
Securely protected by the client’s chosen username and password, the web-based system provides long term data storage and offers the client with world-wide access to the data and control of the system from any web-enabled device.
This also means the client no longer needs a dedicated PC and software license to monitor their ICCP system. Management and control of M275 Tipner Interchange Bridge ICCP assets is now more economic, easier, quicker and more reliable with the PowerView CP solution.
The new monitoring system, which is the first use of Omniflex equipment for a reinforced concrete structure in the UK, was installed and successfully re-commissioned and will subsequently be monitored for a period of 52 weeks by CCSL.
For further information on Omniflex visit www.omniflex.com
CLM Construction was commissioned by Kier Highways to complete concrete repairs and an ICCP scheme in Stoke on Trent for Highways England.
The Campbell Road River Bridge carries the A5006 over the River Trent adjacent to the A500. Water contaminated with chlorides was found to be leaking through the longitudinal and transverse bridge joints onto the supporting crossbeams and columns. The ensuing corrosion, delamination and spalling of the structure required sustainable intervention.
The scheme presented a number of challenges including restricted access, environmental considerations, working within an active flood plain, road closures, temporary works and site security. All posed significant difficulties that required a detailed and robust plan of action.
Despite the site restrictions encountered, CLM was able to successfully deliver the project within programme, completing all concrete repairs in accordance with strict design tolerances, installing and commissioning a mesh anode CP system on multiple structural elements and finally completing the works with a uniformed sprayed concrete finish. All this was achieved whilst maintaining public access and minimising disruptive road closures.
As one of few available day-time working sites on the Area 9 network, Campbell Road Bridge became subject to numerous site visits and audits from senior personal in Kier Group and Highways England, where the project was well received and gained excellent scores and reviews. This contributed to CLM/Kier through Highways England receiving a prestigious Blue Star award.
Independent tests have confirmed that Flexcrete’s Cementitious Coating 851 provides an effective barrier to chlorides for at least 28 years.
In 1988, a 2mm thick film of Cementitious Coating 851 was applied to a concrete slice and sealed in a chloride ion diffusion cell. It is still going strong some 28 years (10,179 days) later. Ongoing tests carried out at the VINCI Technology Centre show that the barrier properties of 851 have not changed after a test period spanning the ongoing 28 years.
Cementitious Coating 851 is a two component, waterborne cementitious modified polymer coating which was originally introduced by Flexcrete in 1985. It remains one of the most effective products for providing structural protection against chloride attack. 851 is specified on both existing and new structures to waterproof concrete, reinstate concrete cover and provide an effective barrier to chloride ingress, amongst many other challenges typically encountered on buildings, infrastructure and structures in sectors such as coastal, highways and water. A 2mm coating of Cementitious Coating 851 is equivalent to 100mm of good quality concrete cover.
Chris Lloyd, Director of Flexcrete Technologies Limited said: “We have been advised that the performance of Cementitious Coating 851 in this test is unparalleled. Not only has the Cementitious Coating 851 shown minimal permeability and constant yet very low diffusion coefficients, Cementitious Coating 851 has not shown any signs of deterioration despite being fully immersed in the chloride solution for over 28 years.”
As part of a two-year, £28 million restoration of London’s prestigious South Bank Centre, Cemplas has carried out extensive concrete restoration and repair works to the internal concrete architectural elements of this globally famous arts venue.
As part of Europe’s largest centre for the arts, attracting more than six million visitors annually, the Queen Elizabeth Hall, Hayward Gallery & Purcell Room are being restored to their original character, which includes renovating board-finished concrete walls and coffered concrete ceilings.
“We’re of course used to working on the outside of landmark buildings,” commented Chris Saunders, Cemplas Estimating & Contracts Manager. “However, the challenge of working on the inside of an iconic building such as the South Bank Centre was one that we absolutely relished.
“With the decorative wooden panelled interior for example, it has been essential to retain exacting humidity controls whilst carrying out concrete cleaning with essentially dry & water-free solutions inside the building”.
Remmers’ Arte Mundit product – a ‘peelable’ poultice – was applied to most surfaces of the exposed internal concrete elements creating an elastic film over the surface which, when peeled away, removed superficial dirt that had built up on the concrete over the years since the centre’s opening back in the 1960s.
The rear walls of the Queen Elizabeth Hall stage also saw black paint removed using the ‘Doff’ method and Tensid Tavec 201 Biodegradable paint remover.
Once cleaned, repairs have had to be carried out to areas of the decorative concrete and blended in to ensure that they are not easily visible.
The Structural Concrete Alliance has announced CCL (GB) Ltd as the winner of the 2016 Structural Concrete Alliance Award for Repair and Refurbishment for its upgrading and strengthening work at National Grid PLC’s Isle of Grain site near Rochester, Kent.
CCL (GB) Ltd provided a solution to replace the existing restrainment system to the outside of the concrete bund walls surrounding the liquid gas steel tanks on the site. The 50,000 cubic m capacity tanks, originally commissioned in 1981, are each surrounded by a reinforced concrete bund wall to provide secondary containment in the event of a rupture of the steel tank.
Second place was awarded to Sika Ltd for its restoration of Poplar Baths in London. Sika provided materials for an extensive programme of concrete and structural repairs to transform the Grade II listed Poplar Baths from a former public baths to a state-of-the-art leisure centre.
Third place went to Volkerlaser for its refurbishment and strengthening of the Woodhouse Tunnel in Leeds. The twin bore, 4 lane tunnel carries the A58(M) beneath Leeds city centre. The scheme involved a complex combination of extensive concrete repair; strengthening by reinforcement addition; extensive sprayed concrete to large areas of repair; the introduction of galvanic anodes in most of the repaired concrete; and traditional formwork and reinforced concrete construction of wall thickening.
The winners were announced by journalist Kate Silverton at the Concrete Society Awards Dinner held at the Grosvenor Hotel, Park Lane, London on 17th November. Commenting on the award, the judges stated:
“The annual Structural Concrete Award aims to identify innovative structural concrete repair and refurbishment solutions that overcome demanding engineering challenges, while advancing technology and understanding.
“Choosing the winners was extremely difficult this year due to the high quality and diversity of the entries. CCL’s solution for the Isle of Grain bund was selected as we were impressed by the innovative approach to safely detensioning the existing wire system, which we recognised as being extremely technically challenging.
“Sika’s sympathetic restoration of Poplar Baths and the complexity of the logistics required in Volkerlaser’s refurbishment of the Woodhouse tunnel served to highlight the innovation and flexibility our specialists must offer in developing repair and refurbishment solutions”
The Structural Concrete Alliance publishes a quarterly E-Bulletin providing the latest industry updates and news from members of the CRA, CPA and SCA, as they occur.
Formed in 1989, the CRA is committed to promoting and developing the practice of concrete repair and allied disciplines, as well as advancing education, technical training and health & safety matters in this specialist construction sector.
The Corrosion Prevention Association represents consultants, contractors and manufacturers working in the field of corrosion prevention for reinforced concrete and masonry encased steel.
Sprayed Concrete Association (SCA) represents leading contracting and manufacturing companies engaged in sprayed concrete.Tweets by @SCAlliance3