Forest communication network consists mainly of dirt roads. Technical problems with forest roads transport occur especially for these dirt roads which are constructed on cohesive topsoil. Lignite fly-ash may be utilized for successful stabilization of cohesive topsoil dirt roads. The pavements stabilized with fly-ash often perform unsatisfactorily under heavy loads and failures are noted as a result. The research described in this paper aimed at developing technical solution for reconstruction of road pavements constructed with admixture of fly-ash and fly-ashslug respectively. Bearing strength variability of fly-ash-soil and fly-ash-slag-soil mixes after failure and application of repair method were considered. Crushed then re-compacted with addition of stabilizer soil mixes as influenced by period and conditions of binding were tested. The stabilizers utilized for testing were both active fly-ash of lignite group IIIC and coke blast furnace slag. Two varieties of mixes were tested. These varieties were sandy clay mixed with addition of 14 % lignite fly-ash and the mixture of 10 % lignite fly-ash and 10% furnace slag respectively. The samples were crashed and re-compacted after 14- and 42-day period of curing in optimal and air-dump conditions. After sample curing deformation modules were measured with the utilization of VSS press. The deformation ...
