MORPHOLOGICAL EVALUATION OF COMPACTED BITUMINOUS MIXTURES

MORPHOLOGISCHE BEURTEILUNG VERDICHTETER BITUMINOESER MISCHUNGEN

THE OBJECT OF THE RESEARCH IS TO DEVELOP A METHOD ENABLING THE EFFECT OF VARIABLE COMPACTION ON THE ARRANGEMENT OF THE THREE COMPONENTS MINERAL, BITUMINOUS MORTAR AND VOIDS TO BE ASSESSED. THE MORPHOLOGICAL ASSESSMENT IS MADE ON CUT SECTIONS. EVALUATION (BOTH VISUAL AND STATISTICAL) IS CARRIED OUT BY MEANS OF A QUANTITATIVE IMAGE ANALYSER (QUANTIMET 720/30). MANUFACTURE OF THE CUT SECTIONS: DRILLED CORES ARE IMPREGNATED WITH SYNTHETIC RESIN (DRYING OF THE SAMPLE, EVACUATION, FLOODING, VACUUM, PRESSURE, HARDENING), CUT, AND GROUND WHILE FROZEN. A FLUORESCENT DYE MIXED INTO THE SYNTHETIC RESIN ENABLES THE VOIDS TO BE CONSIDERED UNDER ULTRA VIOLET LIGHT. THE CONTRASTING OF MINERAL AND BITUMINOUS MORTAR IS DIFFICULT AS THE MINERAL RUNS THROUGH ALL THE GREY STAGES.