Laboratory and field tests with stabilisation of a base layer using inplace milling

Abstract

Stabilisation of base layers using in place milling and foam bitumen is a very cost efficient method for rehabilitation of worn asphalt surfaced road and upgrading of gravel roads to paved surface. This method has been used successfully in Norway using mostly 3 - 5 % foam bitumen [Skoglund and Bakløkk, 2002]. To investigate use of less amounts of bitumen and an alternative stabilisation agent a field test was established. In connection to the field test extensive laboratory testing was performed. All the test sections has so far performed very well and no significant damages or differences between the test sections could be observed. The laboratory tests show that all the stabilised samples get a high increase in resistance against permanent deformations. The samples stabilised with 2 % bitumen was not significantly weaker than the ones stabilised with 4 %. The samples stabilised with DUSTEX showed a very high increase in both resilient modulus and resistance against permanent deformations after curing. However, more research is needed to verify the durability of this method of stabilisation, especially for use when the material is exposed to frost or high degree
of saturation. (Støtterud and Dahlen, 2002)