There were celebrations at Thermal Road Repairs (TRR) HQ in Crewe when the patent for its innovative longitudinal joint repair system arrived last month. It has taken the team years of hard work and investment to get to this point.
“It’s fantastic to finally receive confirmation that our system is unique – and that it’s protected,” says TRR director Aidan Conway. “The patent covers both the technology and the process, which is quite unusual.”
Work on the system began back in 2014. Thermal Road Repairs was talking to Highways England about the problem of failing longitudinal joints. “Because we usually lay one lane at a time in the UK, the joint between the two lanes is a weak point where cracks and later holes can form,” says Conway.
TRR invented a machine which heats the material either side of a joint and re-uses any failed or failing materials, lifting and re-mixing it with a small quantity of new asphalt, so that the road surface is bonded homogeneously across the former joint zone. Standard repair techniques tend to involve planing out a narrow trench and laying new material, solving the immediate problem, but creating two new joints and potential weak spots and generating waste materials to be carted away. Other methods include screeding a proprietary temporary flowable repair material into the failed joint. The TRR system reflects the company’s ethos – repairing asphalt with asphalt and eliminating joints.
Just like TRR’s other technologies, the benefits of the longitudinal joint repair system are both financial and environmental. Repairs can be carried out at a higher rate, causing less disruption to drivers. The joint will not fail again before the whole road surface does, reducing future maintenance intervention costs and the carbon emissions associated with them. And, because it recycles existing material, the carbon footprint of the repair work itself is low.
That very first machine was used on the M62 back in 2015 and worked well, although it wasn’t pretty, according to Conway: “It looked like a big, green UFO, and took around one hour to set up after arriving on site on a low loader.”
Since that time, TRR has invested hundreds of thousands of pounds in R&D. The current iteration of the longitudinal joint repair system involves two neat heater units that are mounted on the side of a a modified truck which is driven along the joint at a speed of between 2 and 3 metres per minute.
And now, the patent is not TRR’s only reason to celebrate. It is currently preparing to tackle a number of longitudinal joint repair schemes for a key government client.