Conclusion

Untreated granular materials have been widely used to produce subgrades. As a result, in-place soil treatment with hydraulic binders has become the norm in all regions where good-quality granular materials are in short supply. The development of in-situ soil treatment with lime and hydraulic binders was made possible by two advances.

The first concerns equipment, particularly in-place spreading and mixing equipment, which has made considerable progress in terms of power and precision. The second is the development of hydraulic road binders (LHR) specially adapted to different soils.

In addition, experience has shown that the higher the bearing capacity of the subgrade (PF3 or PF4, mainly due to the treatment of in-situ soils with hydraulic binders), the higher the compaction and mechanical performance characteristics of the pavement base...