Utilization of Waste Glass Powder and Glass Composite Fillers in Asphalt Pavements
Table 3
Details of characterization properties of fillers.
Filler property
Glass powder (GP)
Hydrated lime (HL)
Stone dust (SD)
Inferences
Specific gravity
2.370
2.363
2.698
GP and HL have lower specific gravity than SD, and thus they occupy larger volume in asphalt mix in comparison to SD. Hence mixes containing GP and HL has lower OAC than conventional asphalt mixes containing SD.
Methylene blue value (g/kg)
1.25
0.25
3.25
All fillers have low MBV (less than 10) which indicated the presence of lower harmful clay content per unit weight of material.
German filler value (g)
75
35
85
HL and SD were found to have lowest and highest porosity/fractional voids per unit weight, respectively.
Fineness modulus
4.66
2.93
5.38
SD and HL were found to be coarsest and finest fillers, respectively.
D50 (µm)
19
9
21
Particle shape and texture (SEM)
Angular particles with smooth texture
Subangular and granulous particles with a rough texture
Angular particles with smooth to rough texture
Particles with rough texture may negatively affect workability and can also cause higher asphalt absorption.
Absence of any harmful expansive clay minerals. SD and HL consist of dolomite and Portlandite, respectively, which is a calcium-based water-insoluble mineral having good asphalt adhesion. Quartz is associated with poor moisture sensitivity.
Hydrophilic coefficient
0.81
0.75
0.77
All materials displayed a higher affinity towards asphalt in comparison to water.
