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.

This article presents a novel potential bio-based rejuvenator derived from waste pig fat (WPF) for use in recycled asphalt applications. To achieve this purpose, the impact of different doses waste pig fat (e.g., 0, 3, 6, and 9 wt.% WPF) on the reclaimed asphalt pavement binder (RAP-B) performance is investigated. The unmodified and WPF-modified asphalts are characterized by means of Fourier-transform infrared spectroscopy (FT-IR), thin-layer chromatography–flame ionization detection (TLC-FID), scanning electron microscopy (SEM), atomic force microscopy (AFM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Physico-rheological properties of asphalt blends are assessed through Brookfield viscometer, softening point, penetration, and dynamic shear rheometer (DSR) tests. TLC-FID data highlighted that incremental WPF addition into RAP-B restored its original balance maltenes-to-asphaltenes ratio; finding which was supported by FT-IR analysis. SEM disclosed that WPF has a great compatibility with the aged asphalt. AFM observations showed that grease treatment induced a decline in surface roughness (i.e., bee structures) and a rise in friction force (i.e., para-phase dimension) of RAP binder. TGA/DSC studies revealed that the bio-modifier not only possesses an excellent thermal stability but also can substantially enhance the binder low-temperature performance. Empirical and DSR tests demonstrated that WPF improved the low-temperature performance grade of RAP-B, reduced its mixing and compaction temperatures, and noticeably boosted its fatigue cracking resistance. The rejuvenation of aged asphalt employing WPF is feasible and can be an ideal approach to recycle both of RAP and waste pig fats.

Over the last decade, unexpected and sudden pavement failures have occurred in several provinces in South Korea. Some of these failures remain unexplained, further illustrating the gaps in our knowledge about binder chemistry. To prevent premature pavement distress and enhance road performance, it is imperative to provide an adequate characterization of asphalt. For this purpose, the current research aims at inspecting the chemistry, microstructure, thermal, and physico-rheological properties of two types of asphalt, namely petroleum asphalt (PA) and natural asphalt (NA). The binders were extensively investigated by using elemental analysis, thin-layer chromatography with flame ionization detection (TLC-FID), matrix-assisted laser desorption ionization time-of-fight mass spectroscopy (MALDI-TOF-MS), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy (RS), Nuclear magnetic resonance spectroscopy (¹H-NMR), ultraviolet and visible spectroscopy (UV-VIS), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), penetration, softening point, ductility, and viscosity tests. The findings of this research have revealed the distinct variations between the chemical compositions, microstructures, and thermo-rheological properties of the two asphalts and provided valuable knowledge into the characteristics of the binders. Such insight has been effective in predicting the performance or distress of road pavement. This paper will, therefore, be of immediate interest to materials engineers in state highway agencies and asphalt industries.

This research aimed at assessing the content and the functional properties of phytohemagglutinin (PHA) in different varieties of beans widely consumed in Tunisia through soaking, cooking, autoclaving, germination, and their combinations. This study was carried out on three varieties of white beans grown in different localities of Tunisia, namely Twila, Coco, and Beldia, as well as on imported and local canned beans. All bean samples underwent biochemical and immunological evaluation by employing several techniques such as indirect competitive enzyme-linked immunosorbent assay (ELISA), hemagglutinating assay, Ouchterlony double immunodiffusion, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Biochemical and immunological analyses indicated that raw dry beans contained a considerable amount of proteins and PHAs. ELISA demonstrated that soaking, either in plain water or in alkaline solution, caused an increase in the concentration of PHA. A slight increase of PHA was produced equally by germination during 4 days in all bean varieties. Cooking or autoclaving of presoaked beans resulted in a complete disappearance of PHA. ELISA test also proved that both imported and local canned beans contained fingerprints of PHA. Hemagglutination assays showed that not only cooked and autoclaved presoaked beans lacked the ability to agglutinate red blood cells but also autoclaved unsoaked beans did. In agar gel immunodiffusion using rabbit anti-PHA serum, raw, soaked, cooked unsoaked, and sprouted beans gave precipitin arc reactions, indicating that PHA existed in immunoreactive form in the tested seeds. SDS-PAGE electrophoretograms showed protein isolates of Twila and Beldia beans to have different profiles through soaking, cooking, and autoclaving processes. This work revealed that the combination of soaking and cooking/autoclaving was the best way in reducing PHA content and its activity in all bean varieties when compared with germination.