Potential of Waste Oyster Shells as a Novel Biofiller for Hot-Mix Asphalt

Abstract

This paper reports the use of waste oyster shells as a novel biofiller for hot-mix asphalt (HMA) pavement applications. The effects of different fractions (e.g., 0, 5, 10, 15 wt %) of oyster shell powder (OSP) on the bitumen performance were investigated. The chemical properties of unfilled and OSP-filled asphalts were characterized by means of thin layer chromatography-ionization detection (TLC-FID), Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Thermal characteristics were examined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Physical and rheological properties were assessed through penetration, softening point, ductility, and dynamic shear rheometer (DSR) tests. Results showed that OSP addition increased the resins content, as well as the stiffness of blends. No obvious reactions have occurred between the filler and the asphalt. A higher dose of OSP altered the morphology of the binder, whereas lower and intermediate doses improved its thermal stability and enhanced its low-temperature, rutting, and fatigue performances with respect to the plain asphalt. Overall, the waste oyster shells could be used as filler substitute, not only to improve the quality of road pavements but also to reduce the cost of their construction and solve the waste disposal problems.

Application of Zeolite Tuffs as Mineral Filler in Warm Mix Asphalt

“…Obtained research results illustrate that the types of fillers used in an amount of 5% in relation to the mass of asphalt did not significantly affect the physical properties of the tested asphalt such as penetration, softening point and thermal sensitivity. Increasing the amount of filler, a wider range of changes could be expected, as shown by studies conducted by Nciri with oyster shell powder (OSP) in the amounts of 5%, 10% and 15% [6].…”

“…As noted by Nciri et al, this phenomenon is caused by the stiffening of asphalt binder after mixing with dust fraction. It consists of the following processes [6]:…”

“…An insufficient amount of filling material may result in reduced rutting resistance. In turn, too much filler causes the asphalt mix to become more fragile and susceptible to low-temperature cracking [6].…”

Evaluation of Chicken Feather and Styrene-Butadiene/Chicken Feather Composites as Modifier for Asphalts Binder

“…This behavior is attributed to the interaction between the amino acid groups of the keratin structure and the polar compounds of the asphalt, such as resins and asphaltenes. These interactions can be explained by the presence of three different mechanisms: (1) existence of rigid inclusions, (2) filler-asphalt interfacial effects and (3) reinforcement due to the filler volume produced by particle interaction [8,22]. Keratin has a complex structure that leads to an increased mechanical stability in the asphalt blend [23].…”

“…One of the most conventional and easy ways to produce modified asphalts is preparation by hot mixing, since it allows the addition of differently shaped and sized particles, which are responsible for the viscoelastic behavior of the final blend due to the physical interactions between the modifier particles and the asphalt components [6,7]. Previous works have reported the successful addition of oyster shells as filler substitutes [8]. Various waste materials, such as egg shell powder, have also been evaluated as sustainable modifiers, which has resulted in discovering promising modifiers for asphalt mixtures [9].…”