CONTRIBUTION TO THE UPDATING OF THE DIRECTIVES FOR ROADBASES STABILIZED WITH HYDRAULIC BINDERS

CONTRIBUTION A LA REVISION DES DIRECTIVES DES ASSISES TRAITEES AUX LIANTS HYDRAULIQUES

THE DIFFERENT DIRECTIVES FOR THE CONSTRUCTION OF GRAVEL ROADBASES STABILIZED WITH HYDRAULIC BINDERS WERE ESTABLISHED USING DATA (STUDIES, INVESTIGATIONS AND OBSERVATIONS) OF AT LEAST 5 YEARS OF AGE. THE OBJECTIVE OF THE RESEARCH IS TO FIND FRESH DATA NECESSARY TO THE UPDATING OF THESE DIRECTIVES. THE THREE MAIN IMMEDIATE OBJECTIVES ARE: TO DEFINE THE PERFORMANCE LEVELS TO BE ATTAINED FOR EACH CATEGORY OF STABILIZED ROADBASE; TO STANDARDIZE AND OPTIMIZE STANDARDS GOVERNING AGGREGATES; TO DETERMINE THE DISPERSION THRESHOLDS NOT TO EXCEED DURING ROAD CONSTRUCTION. IN 1979 IT IS PLANNED: TO STUDY VARIATIONS IN THE MECHANICAL CHARACTERISTICS OF GRAVEL-CEMENT AS A FUNCTION OF FLUCTUATION IN CEMENT PROPORTIONING, MOISTURE CONTENT AND DENSITY; TO STUDY THE MECHANICAL CHARACTERISTICS OF GRAVEL SLAG WITH A FULL CURVE, WITH VARYING FINES CONTENTS. A SUMMARY WILL BE PREPARED OF OBSERVATIONS ON CONTROLS IN FIXED PLANTS MANUFACTURING GRAVEL AND SAND-SLAG IN THE PARIS REGION.