Page 160 - Mechanics of Asphalt Microstructure and Micromechanics
P. 160

152   Ch a p t e r  Fiv e


                 (d) Alternative version
                                                         2 ⎡
                                                                          2
                                                             '
                                 +
                                               +
                                                    +
                       Ec = Va pEa VmpEm +( Va s Vms Vvs) ⎢ Va s +  ( Vms + VVvs) ⎤ ⎥  1 −
                             '
                                             '
                                                          ⎣  Ea    VmsEm   ⎦
                                                       ⎡ Va'  ( Vm Vv) ⎤  −1
                                                                +
                                                                    2
                            Ec =  Pc Va Ea VmEm +(1 −  Pc)⎢  +       ⎥          (5-157)
                                        +
                                  (
                                              )
                                     '
                                                       ⎣ ⎣  Ea  VmEm  ⎦
                                              ⎛   VFM Em⎞   P 1
                                                       ×
                                              ⎜ ⎝  P +     ⎟ ⎠
                                                0
                                          Pc =      VMA'
                                                 ⎛ VFM Em⎞  P P 1
                                                       ×
                                              P + ⎜        ⎟
                                               2  ⎝  VMA'  ⎠
                 Simple three-phase system of aggregate, asphalt binder, and air voids:
                                                      ⎡ Va  ( Vb Vv) ⎤ ⎤  −1
                                                               +
                                                                   2
                              Ec =  Pc VaEa VbEb +(1 −  Pc)⎢  +     ⎥           (5-158)
                                        +
                                   (
                                              )
                                                      ⎣ Ea   VbEb   ⎦
                 Incorporate film thickness:
                                                       ⎡ Va  ( Vb Vv) ⎤ −1
                                                               +
                                                                   2
                             Ec =  Pc VaEa VbEb +(1 −  Pc)⎢  +      ⎥           (5-159)
                                        +
                                   (
                                              ')
                                                       ⎣ ⎣ Ea  VbEb'  ⎦

                 Effective binder modulus:
                                                 tEbE
                                         Eb' =    F   g
                                              t ( − t E + t Eb                  (5-160)
                                                   )
                                               F  T  g  T
                 Comparison between model predictions and experimental results indicates that the
              parallel version of model AC properties is better.
                 Luo and Lytton (2009) made use of the Hashin and Shtrikman lower bound and
              extended it into general coupled self-consistent formulations.
                                            n
                                           ∑ c i  K −  K  * *  = 0              (5-161)
                                                 i
                                                K +
                                           i=1  3  i  G
                                                    *
                                        n
                                               (
                                        ∑    cG −  G )   = 0                    (5-162)
                                                 i
                                              i
                                               *
                                        i=1  * 9 K + 8 G  *
                                          G   *    *  + 6 G i
                                             K + 2 G
                 For the three-constituent asphalt mixture, the above formulations become:
                                 cK −  K )  cK −  K )  cK −  K )
                                         *
                                                              *
                                                   *
                                                        (
                                   (
                                             (
                                  1  1    +  2  2    +  3  3    =  0            (5-163)
                                  3 K + G *  3 K +  G *  3 K + G *
                                    1          2          3 3
                           cG −  G )        cG −  G )        cG  − G )
                                                                    *
                                                   *
                                  *
                                                               (
                                              (
                             (
                            1  1       +     2  2       +     3  3       =  0   (5-164)
                                              +
                             *
                                             *
                          9 K +  8 G *     9 K + 8G *       9K  *  + 8G *
                        G *  *   *  +  6 G 1  G *  *  *  + 6G 2  G  *  *  *  + 6G 3 3
                           K +  2 G         K  + 2G          K  + 2G
   155   156   157   158   159   160   161   162   163   164   165