The primary objective in soil stabilization is improving on‐site materials to create a solid and strong sub‐base and base courses for further construction activities. Classic stabilization methods for road structures imply soil mixing with cement or lime, depending on the soil types found on‐site. Although widely used, these stabilization methods fail to provide hydrophobic properties for the stabilized layer, thus being vulnerable to road failure from water penetration or heavy frosts by inhibiting the ingress of water into the treated layer. Dorosol© is a hydraulic binder which combines cement and lime in order to improve and consolidate cohesive soils for embankments and subgrade stabilization, providing a superior protection against water penetration. This paper presents the improvement of physical and mechanical parameters of a silty clay from Cluj‐Napoca, by using two types of Dorosol©, C30 and C50 suited for treating heavy plastic clayey soils. Percentages of 2.5, 3, 3.5, 4 and 4.5 were used for creating stabilized soil samples for both types of binder.