Utilization of a natural pozzolan as the main component of hydraulic road binder

This paper deals with the utilization of a natural pozzolan as the main component of Hydraulic Road Binder (HRB). A study of its reactivity in presence of lime and gypsum leads to a proposal for an optimized binder composed of 80 wt% pozzolan, 15 wt% lime and 5 wt% gypsum. The characteristics of this binder were tested on mortars and on samples of treated soil and the results lead to the conclusion that it is possible to produce an HRB rich in pozzolan and without cement that can efficiently stabilize clayey soils.

► The characteristics of the pozzolan were comparable to those found in the literature.
► The optimized binder was composed of 80% pozzolan, 15% lime and 5% gypsum.
► The results obtained on samples of treated soils were satisfactory.
► It is possible to produce an HRB rich in pozzolan and without cement.
► HRB characterization on standard mortars is not appropriate.