Thin surfacings have been developed in France that are considered a cross between conventional thin-wearing course surfaces and thick surface dressings. Two of these materials, Safepave (or Euroduit) and UL: M, are now being offered in the United Kingdom. A series of road trials are tinder way to assess their benefits and any possible negative aspects. The trials have two main objectives: to compare the performance of these thin surfacings with existing materials of known perfomiance and to assess their effectiveness as resurfacing materials. To compare their performance, the first aim, the surfacings were laid in sections alongside sections of rolled asphalt wearing course, racked-in surface dressing, and slurry surfacing. To assess their effectiveness, the second aim, Safepave was laid over concrete highways using different treatments at the joints to delay reflective cracking. Trials were conducted on various types of road, including a motorway, major-trunk dual carriageway, rural-trunk and urban dual carriageway. Measurements made on the surf acings included visual assessment, skid resistance (Sideway-force Coefficient Routine Investigation Machine and rake-force trailer), texture depth (sand patch and sensor-measured), rutting, longitudinal profile, and noise. Use of thin surfacings in the United Kingdom is discussed and results of the trials to qate are reported. Usefulness of these materials, as well as the conditions under which they should prove effective compared with other currently available materials surfacing is also considered.

As the volume and loading of road traffic has risen and the disruption costs of making repairs has increased, new surfacing materials are being developed in many parts of the world that enable roads to remain maintenance free longer or that can be applied to roads in a manner that minimizes traffic disruption. New materials include thin surfacings, several of which have been developed and approved in France through the A vis Technique system. Some of France's thin surfacings are being brought to the United Kingdom through licensing agreements with UK contractors. Thin surfacings are classified as a singie layer of material, laid and compacted using paving machines and rollers. Such surfacings are considered a cross between thin wearing courses and thick surface _dressings. Their typical thicknesses range between 15 mm and 30 mm, and it is possible to apply greater thicknesses in localized areas. The advantages to using thin surfacings are that they provide the appropriate level of skid resistance and also regulate the profile (to a limited extenO while minimizing the loss of headroom at overbridges and the need to raise ironwork. As with veneer surfacings, such as surface dressing and slurry seals; thin surfacings should be used only where supporting pavement is structurally adequate. The surfacings have all the advantages of a surface dressing, without the disadvantage of the after-care service that is required for surface dressing. They also are able to make uneven surfaces regular and can be laid under weather· conditions that surface dressing cannot.