TITLE:
Development of a Dynamic Modulus Prediction Model for Hot Mixture Asphalt and Study of the Impact of Aggregate Type and Its Electrochemical Properties
AUTHORS:
Mouhamed Lamine Chérif Aidara, Makhaly Ba, Alan Carter
KEYWORDS:
Dynamic Modulus, Mineralogical, Basalt of Diack, Quartzite of Bakel, Limestone of Bandia, Zeta Potential, Silica
JOURNAL NAME:
Open Journal of Civil Engineering,
Vol.10 No.3,
July
24,
2020
ABSTRACT: The most famous model known in prediction of dynamic modulus for asphalt concretes is the Witczak and Hirsh models.
These models didn’t use the mineralogical and chemical properties of aggregates.
Witczak models used the passing or refusal percentage to sieve diameters and Hirsh
model used the volumetric
analysis. All models developed until now considered that the aggregates were geotechnical
conforming to standards. In this study the first mineralogical and chemical properties
were considered through the percentage of silica in the rock source of aggregates
and the electric aggregate particles charge zeta. Dynamic modulus values used for
regression process are determined from complex modulus test on nine asphalt concretes
mix designed with aggregate types (basalt of Diack, quartzite of Bakel and Limestone
of Bandia). Between Twelve initial inputs, the statistical regression by exclusion process keeps only seven parameters
as input for the model. The mineralogical model showed good accuracy with R2 equal to 0.09. The student test on the model parameters showed that all the parameters
included in the model were meaningful with good p inferior to 0.05. The Fisher test
on the model showed the same result. The analysis of the sensitivity of the mineralogical
model to zeta potential showed that the dynamic modulus increases with the positive zeta-potentials and decreases with the negative zeta-potentials. The analysis
of the sensitivity of the mineralogical model to the silica showed that the dynamic
modulus decreases with the increase of the silica.