Abstract:
The quest to developing a universally acceptable mix design procedure
for cold mix asphalt (CMA) is in the spotlight of continuous research. Moreover, the
performance improvement ofCMAcoupled with sustainable construction drives had
witnessed the inclusion of industrial by-products and biomass waste alike in CMA.
Nonetheless, various transportation departments in different countries tailor CMA’s
design to suit their geographic regions’ peculiar challenges.Despite such efforts, mix
designs need to produce laboratory results replicative of service conditions capable
of ameliorating the high void content, weak early strength, and slow rate of strength
gain of CMAs. This study proposed a performance-based mix design based on the
combined result of indirect tensile stiffness modulus (ITSM) and Cantabro loss tests
compared to the standardMarshallmix design. Themixtures contain binary blending
of 1–4% palm oil fuel ash (POFA) with 3–6% granite filler by total aggregate weight
in a fine dense-graded CMA using a polymer-modified cationic quick set (CQS-1h)
and an unmodified rapid set (RS-1K) emulsified asphalt. A gradation with a nominal
maximum aggregate size (NMAS) of 4.75 mm (FGCMA-4.75 mm) was employed.
In addition to Cantabro and ITSM, the designed mix was tested for Indirect Tensile
Strength (ITS), and modified Lottman’s test. Results revealed a significant correlation
between the usual Marshall design with the proposed design based on the established
optimum emulsion contents (OEC). An optimal 3% POFA yielded moistureresistant
mixtures with enhanced mechanical and Marshall volumetric properties in
void reduction, increased stability, and adequate early strength.
