Self-Consistent Micromechanics Models of an Asphalt Mixture

An asphalt mixture is a composite material consisting of three components: asphalt binder, aggregate and air. The mechanical properties of asphalt mixtures are mostly evaluated from empirical approaches that are usually limited to measurement conditions. This paper takes a mechanistic approach by using micromechanics theory for composite materials to develop self-consistent micromechanics models for an asphalt mixture. The mixture analysis method described in this paper is applied to measured properties of an asphalt concrete mixture that is commonly used in Texas. These models are programmed in MATLAB using the System Identification Method and are applied to the analysis of the frequency-dependent magnitudes of viscoelastic properties of an asphalt mixture at different aging periods. The inverse calculation model takes as input the volumetric composition of the mixture and the measured frequency-dependent bulk and shear properties of the asphalt mixture and the binder and extracts from them the bulk and shear properties of the aggregate. The forward calculation model takes as input the frequency-dependent bulk and shear properties of the aggregate and binder and produces the frequency-dependent properties of the asphalt mixture. It has been demonstrated that the inverse and forward operations are in fact the inverse of each other and that the inferred aggregate properties are realistic. These models provide a technique to catalog the properties of aggregate and use them in a computerized determination of the combinations of binders, aggregates and air to produce the desired properties of asphalt mixtures.

[1]  Cédric Sauzéat,et al.  Three-Dimensional Linear Behavior of Bituminous Materials: Experiments and Modeling , 2007 .

[2]  Andrew LaCroix,et al.  Predicting the Resilient Modulus of Asphalt Concrete from the Dynamic Modulus , 2007 .

[3]  Zvi Hashin,et al.  The Elastic Moduli of Heterogeneous Materials , 1962 .

[4]  Robert L. Lytton,et al.  SYSTEM IDENTIFICATION METHOD FOR BACKCALCULATING PAVEMENT LAYER PROPERTIES , 1993 .

[5]  H Di Benedetto,et al.  Micromechanics-Based Model for Asphalt Mastics Considering Viscoelastic Effects , 2006 .

[6]  Robert L. Lytton.  Backcalculation of Pavement Layer Properties , 1989 .

[7]  Richard Schapery,et al.  A method of viscoelastic stress analysis using elastic solutions , 1965 .

[8]  S. Shtrikman,et al.  A variational approach to the theory of the elastic behaviour of multiphase materials , 1963 .

[9]  Zvi Hashin,et al.  Complex moduli of viscoelastic composites—I. General theory and application to particulate composites , 1970 .

[11]  Sung Hoon Jung,et al.  Preliminary Fatigue Analysis of a Common TxDOT Hot Mix Asphalt Concrete Mixture , 2005 .

[12]  R. Hill.  A self-consistent mechanics of composite materials , 1965 .

[13]  S. Shtrikman,et al.  On some variational principles in anisotropic and nonhomogeneous elasticity , 1962 .

[14]  H. Saunders,et al.  Identification of Vibrating Structures , 1982 .

[15]  B. Budiansky.  On the elastic moduli of some heterogeneous materials , 1965 .

[16]  Sung Hoon Jung,et al.  Binder Oxidative Aging in Texas Pavements: Hardening Rates, Hardening Susceptibilities, and Impact of Pavement Depth , 2006 .