Stabilization and Structural Design of Marginal Materials for Use in Low-Volume Roads

The present structural design method available for bitumen emulsion-treated materials is mostly based on the experience of road engineers and does not provide the necessary guidelines for mechanistic analysis and design. Emulsion treatment is being used more frequently to improve marginal materials and rehabilitate existing badly deteriorated road. Research was conducted on the structural performance of emulsiontreated materials under heavy-vehicle simulator (HVS) and laboratory testing. The issues considered included strength, fatigue, and permanent deformation. The results showed that the emulsion-treated material has a two-phase behavior, namely, a precracked phase and a postcracked phase. The tests also showed that the material has a high degree of resistance to permanent deformation. The laboratory tests showed that cement contributes to the strength of the material, whereas the addition of enough emulsion improves the flexibility. The HVS testing data were used to develop preliminary structural design models for fatigue and permanent deformation.