POTHOLES: - CSIR

4.5.5 Medium-depth repair (thin bituminous sub-base, when necessary) should be constructedseals)in the moistened hole to provide continuity of theWhere potholes have formed in thin bituminoussealedpavements as a result of seal damage, loss must be roughened lightly before placement oflayers as far as possible. The top of each layerof bonding with the base or some other surficial the following layer.defect, failure to patch the pothole quickly results inThe asphalt patch at the top of the reconstructeda rapid deterioration of the surface. Enlargementpothole area should not be less than 50 mmand deepening of the pothole will follow, usuallythick and should be constructed as describedinto the base or even sub-base. In these casespreviously with the joins sealed using a wellbondedgeosynthetic strip.the underlying support layers are normally stilladequate, unless the pothole is not patched for anextended period, and do not need deep repair.This type of failure is usually indicated by a lack of4.5.6 Deep repair (thin bituminous seals)severe crocodile cracking of the seal in the failedWhen the pavement is structurally unsoundarea and affects the full base-depth and possiblyor water has entered the pavement structurethe sub-base.at depth, the road surface will usually form adepression, crocodile cracks will appear in theMethodsurfacing and this will start to ravel and spall,In these cases, the damaged volume (and a little forming large potholes. Although these usuallybeyond) must be marked, cut and removed totally affect the base and sub-base, failure to repairand the edges and bottom cleaned to leave a the underlying support material will result in anhard, compacted surface. Layers of crushed stone, inadequate repair.natural gravel or cement-treated material (75 to100 mm thick) to match the existing base (andMethodIn these cases, the damaged volume (and a littlebeyond) must be marked, cut and removed totallyand the edges and base cleaned to leave ahard, compacted surface. Layers of crushedstone, natural gravel or cement-treatedmaterial should be constructed in thePotholessame locations (and to the same60densities) as the existing pavementlayer materials to provide continuityof the layers as far as possible.The top of each layer must beroughened lightly before placementof the following layer.36