At a time when the UK construction sector is falling prey to supply chain issues and the logistical challenges of importing goods from Europe and further field, IKO’s advanced mastic asphalt waterproofing systems are British-made in manufacturing-sites across the UK.

This can drive down lead times, enable better quality control and lower transportation costs. Furthermore, it is sustainable to choose suppliers which manufacture their products in the UK rather than import from abroad.

Fewer miles result in materials with lower carbon emissions. It’s an approach that aligns with National Highways, the new-look builder and operator of the country’s motorways and major roads who aim to bring road maintenance and construction to net-zero emissions by 2040.

IKO strives to minimise its carbon footprint as far as possible and since January 2015 has been involved in a number of emission offsetting projects that contribute to the CarbonZero™ programme run by CO2balance. In a five-year period, IKO has offset 9264.69 tonnes of CO2 – the equivalent of 4343 returns flights to New York - through its involvement in

an energy efficient stove project in Kenya and a bore hole rehabilitation project in Uganda, activities which reduce CO2 emissions from the burning of firewood.

Case study: Laggan, Torvean, and Benavie swing bridges

A crucial component of the IKO Road range, IKO Permatrack Bridge Surfacing mastic asphalt is a long-established surface course for steel bridges. It provided the waterproof surface course finish for three swing bridges based in the Scottish Highlands.

Located in Laggan, Inverness and Fort William, each structure was in need of a proven surface solution which offered a voidless application without the need for compaction. IKO Permatrack Bridge Surfacing mastic asphalt proved more than capable for the task.

Challenges

For each project, IKO Permatrack Bridge Surfacing was supplied ready-to-lay for installing contractor BriggsAmasco. This in itself presented a challenge due to the projects’ remote location. To prevent the products’ consistency from altering in transit, IKO had to ensure the material’s mix composition and temperature control were correct at the point of manufacture.

This meant that 11 hours after leaving IKO Grangemill’s production plant, the IKO Permatrack Bridge Surfacing solution was in prime condition upon its arrival on site.

Collaboration

A close working relationship between IKO and BriggsAmasco was crucial to the success of each swing bridge project. The collaborative effort proved particularly useful to ensuring material deliveries to Torvean Swing Bridge arrived on the agreed date despite severe snowstorms causing disruption throughout the region at the time.

The fact that the hot charge works arrived safely and ready-to-use despite the poor weather and long journey involved was due in no small part to IKO employing its haulier, Punchards Haulage Ltd, to supply the additional drivers and vehicles required.

IKO Materials

IKO Permatrack Bridge Surfacing: manufactured under the controls of ISO 9001 Quality Management System and in accordance with the requirements of BS EN 13108 Part 6, a harmonised European standard which specifies the requirements for mixtures of the mix group mastic asphalt for use on roads, airfields, and other trafficked areas. Mastic Asphalt is used for surface courses, binder courses, protection layers, inter-layers for bridges, tunnels and troughs.

Applications

• Torvean Swing Bridge, Inverness: Approximately 32 tonnes of IKO Permatrack Bridge Surfacing were supplied and installed across a 320m2 area for this new bridge construction, which was carried out by Briggs Amasco for Leiths (Scotland) Ltd, who were a subcontractor to R J McLeod. BriggsAmasco installed nominal 40mm IKO Permatrack Bridge Surfacing on a PMMA liquid waterproofing system which included a suitable tack coat.

• Laggan Swing Bridge, Laggan: A total of 30 tonnes of IKO Permatrack Bridge Surfacing was supplied for this refurbishment project. The programme involved stripping the existing surfacing and installing 40mm IKO Permatrack Bridge Surfacing mastic asphalt on nominal 5mm IKO Permatrack PSB rubberised bitumen waterproofing. Whilst the mastic asphalt was still hot, 6mm bitumen-coated chippings of a high PSV aggregate were broadcast into the surface to provide texture and skid resistance.

• Benavie Swing Bridge, Fort William: Approximately 7.5 tonnes of IKO Permatrack Bridge Surfacing were supplied. This involved a series of 40mm thick patch repairs to replace the existing and bring the surfacing back to an acceptable standard. The works to the Benavie and Laggan bridges were carried out under the watchful eye of the client BEAR Scotland.

Conclusion

For each of the above projects, IKO Permatrack Bridge Surfacing proved its quality in terms of its excellent usability and in-situ performance. Unlike conventional road asphalts IKO Permatrack Bridge Surfacing can be laid relatively thinly, either by hand or suitable laying equipment at a nominal 40mm, whilst contributing to a surface’s overall weather tightness.

In total, 69.5 tonnes of mastic asphalt were installed on the above projects, which equates to offsetting 10.88 tonnes of CO2.

With IKO Permatrack Bridge Surfacing, specifiers are also provided with assurances from test data for Resistance to Fatigue, Indirect Tensile Stiffness Modulus, Retained Tensile Strength (Freeze/Thaw), Bond Strength.

Such peace of mind is testimony to this product’s tried-and-trusted credentials in bringing a wide range of projects to a successful conclusion over many years, with its quality likely to be keeping our roads and bridges safe and operational for many years to come