Dorset News Release

March 2004: Asphalt specialist Bituchem have developed a lower-cost hot emulsion surface dressing system capable of saving cash strapped local authorities thousands of pounds each year through the reduction of failure related remedial work. The emulsion surface dressing system, which includes latest binder technology from BP Bitumen, has already resulted in substantial cost savings for Dorset County Council who, after switching to the new product, successfully surface dressed 1,000,000m2 of road with zero failure after the first year of installation. The success is a considerable achievement for Bituchem who recovered from a serious fire at their Gloucestershire manufacturing plant five years ago but are now competing against major players in a highly-competitive industry with a combination of lower cost technology and dedicated customer support, a contributing factor to Dorset County Council’s recent decision to extend Bituchem’s tender from one to three years. Significantly, for the nearly 200 Highway Authorities in England, who are under increasing pressure to raise performance and efficiency standards, particularly in the road maintenance sector, replicating Dorset’s experience with Bituchem could help reduce road maintenance costs throughout the UK. Total expenditure on routine local road maintenance in England in one year is currently around £700 million. “We estimate that by using the Bituchem system we are saving approximately £17,000 each year,” said Tom Knott, Contracts Manager for Dorset Works Organisation. “The average failure rate for emulsion surface dressing is approximately between 1 and 2 per-cent. This is taken for granted. The cost to re-dress 10,000m², for example, would be about £8500 but this could be doubled to cover loss of production. “We had experienced problems over a number of years with previous suppliers of emulsion surface dressing, largely because of a lack of technical support and product reliability. Binder technology is very complex, even base binders with the same viscosity can have different binder properties, so good back-up is essential.” Bituchem, who answered the growing industry requirement for polymer modified emulsions by harnessing the potential of BP Bitumen’s Polymer Modified Bitumen (PMB), won the Dorset tender due to a combination of competitive prices and a commitment to provide a reliable support in product and monitoring of the contract. “We supplied a combination of K1-70 emulsion and Polbit, an intermediate polymer bitumen emulsion, to both a static tank and site deliveries,” said Bituchem Managing Director Roger Lord. “ Our success in Dorset can be attributed to a combination of lower cost, reliable product and comprehensive and responsive technical support.” Editors Notes: All road surfaces wear out over time and need maintenance to keep them in a safe condition. Surface dressing is a simple and cost effective way of improving the road surface and can prevent more expensive repair work being needed later Surface dressing is still a valuable way of repairing a road surface that is showing signs of wear. If it is done when the road first starts to wear it can prevent the need for the surface to be removed and replaced or for the road to be completely rebuilt, both of which are very expensive. Surface dressing involves spraying the existing road with a coating of hot bitumen emulsion and then covering it with stone chippings. The chippings are rolled into the bitumen to form a water resistant, protective layer with improved skid resistance. The work can only be done in the summer, when the weather is warm and dry, because the bitumen will not stick to the road in cold or wet conditions. As soon as the bitumen has set, the road is swept to remove any excess chippings. The county’s roads are regularly assessed to record their condition. Surveys are carried out to measure skid resistance and checks are made for cracking and subsidence. When roads begin to show signs of wear, the skid resistance drops or small cracks appear, surface dressing can be used to extend their life. Surface dressing costs just a fifth of the cost of resurfacing. In practice this means that 5 miles of roads are dressed for the cost of resurfacing just 1 mile The only way to make sure that all of the road is properly covered is to put down more chippings than will eventually remain on the finished road. As soon as the bitumen has set, the excess chippings are swept up. Traffic may be allowed back on the road before the loose chippings are removed, both to reduce congestion and because slow moving vehicles help to embed the chippings. Advisory speed restriction signs are left out for a few days after surface dressing both to protect the new surface and to prevent damage to vehicles. If the chippings do not stick because of a problem with the bitumen or changes in the weather, extra sweeping or ‘dusting’ is carried out to minimise the effect on traffic.

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