A probabilistic model for field density distribution of asphalt pavements

ABSTRACT

The field density of as-constructed asphalt pavements usually exhibits considerable variability. Understanding and quantifying this variability is of crucial importance for building more reliable and durable pavements. This study investigates the probability distribution of the field density based on an analytical model of gyratory compaction. The model is derived from mass balance and the transition state theory for the process of aggregate rearrangement. Meanwhile, the variability in the compaction effort is also taken into account. The model is first calibrated by the laboratory gyratory compaction experiments, and is then used to predict the probability distribution of the field density, which is compared with field measurements. It is shown that the probabilistic model can capture the left-skewed and leptokurtic features of the field density distribution. The present model surpasses the commonly used Gaussian distribution for characterising the field density distribution. A parametric study is performed to investigate the effects of the compaction properties of mixture and field compaction effort on the probability distribution of the field density. The model can potentially be used to guide the asphalt mix design for achieving the desired field density.

KEYWORDS:

• Asphalt mixtures
• field density
• gyratory compaction curve
• probabilistic model
• reliability

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data and computer code generated from the study are available from the corresponding author by request.

Additional information

Funding

The authors gratefully acknowledge the support under grant 1003325 WO#106 to the University of Minnesota from the Minnesota Department of Transportation.