Effect of stone-on-stone contact on porous asphalt mixes: micromechanical analysis

Figures & data

Figure 1. The diagram of the homogenisation technique.

Figure 2. Illustration for the MT model.

Figure 3. Configurations of different asphalt mixes.

Figure 4. Illustration of the MT model for PA mixes.

Figure 5. Workflow diagram.

Table 1. Gradation and density of aggregates.

Size (mm)	16	11.2	8	5.6	2	0.5	0.18	0.125	0.063	Filler
% Passing	98	77	44	22	15	14	9	6	4	0
Density (kg/m^3)	2686	2686	2678	2670	2673	2658	2658	2658	2658	2638

Table 2 . The volume fraction of each phase.

PA mixes	Stone-on-stone skeleton	Mortar	Air voids
PA mix-1	0.624	0.197	0.179
PA mix-2	0.66	0.208	0.132

Table 3. Gradation of aggregates in mortar.

Size (mm)	0.5	0.18	0.125	0.063	Filler
Gradation (% Passing)	100	62	39	29	0

Figure 6. Preparation of mortar specimens.

Figure 7. DSR setup for mortar tests.

Figure 8. Setup for the uniaxial cyclic compressive test.

Table 4. Mechanical properties of PA mixes and mortar.

Material constants	Mix	Mortar
Shear modulus	${\mu }_{\mathrm{mix}}^{\ast }={\displaystyle \frac{E_{\mathrm{mix}}^{\ast }}{2(1+{\nu }_{\mathrm{mix}})}}$	${\mu }_{\mathrm{mor}}^{\ast }$
Bulk modulus	${\kappa }_{\mathrm{mix}}^{\ast }={\displaystyle \frac{E_{\mathrm{mix}}^{\ast }}{3(1-2{\nu }_{\mathrm{mix}})}}$	${\kappa }_{\mathrm{mor}}^{\ast }={\displaystyle \frac{2{\mu }_{\mathrm{mor}}^{\ast }(1+{\nu }_{\mathrm{mor}})}{3(1-2{\nu }_{\mathrm{mor}})}}$
Poisson’s ratio	νmix = 0.3	νmor = 0.3
Young’s modulus	$E_{\mathrm{mix}}^{\ast }$	$E_{\mathrm{mor}}^{\ast }=2{\mu }_{\mathrm{mor}}^{\ast }(1+{\nu }_{\mathrm{mor}})$

Figure 9. Predicted results of the stone-on-stone skeleton’s stiffness.

Figure 10. Modified arrangement of the Christensen’s model.

Figure 11. Comparison between $|E_{\mathrm{mix}\mathrm{\_}\mathrm{agg}}^{\ast }|$ and f_aggP_aE_agg.

Figure 12. Comparison between tested $E_{\mathrm{mix}}^{\ast }$ and back-calculated $E_{\mathrm{mix}}^{\ast }$.

Figure 13. The behaviour of the stone-on-stone skeleton at different frequencies/temperatures.

Figure 14. The behaviour of the stone-on-stone skeleton with different amount of compaction effort.

Figure 15. Comparison of stiffness between the stone-on-stone skeleton with mortar and PA mixes.