THE USE OF SAND STABILIZED WITH CEMENT AND AN EMULSION IN ROADBASES

This mixed stabilization method (addition of cement and bituminous emulsion) was tried out to permit the use of sand from the Liore. Laboratory studies were conducted to formulae to be used for the mixture. 4 experimental sections with the following roadbases were also constructed: (1) control gravel-emulsion (0/20) layer; (2) sand-cement-cpal-emulsion; (3) sand-fillerized cement-emulsion; (4) sand-emulsion. To manufacture the sand-cement-emulsion mixtures, a gravel-emulsion plant was used to which a device for cement supply was added. At the laying stage, the compaction ratio was highly satisfactory. The four sections were observed regularly (deflection measurements, recording of influence curves and calculation of the rd product, recording of transverse profile, measurement by means of the lightweight vibrator, core samples). The method proved to be of great interest as regards cracking. Test results led to the recommendation of the following formulae: (1) Loire sand; (2) cpal cement (4%); (3) anionic emulsion overstabilized with 50% bitumen (4 to 5%). /TRRL/