In this study, a detailed investigation on the effect of zinc oxide (ZnO) quantum dots (QDs) embedment on the physicochemical properties of anatase titanium dioxide (TiO2) was conducted. The highly porous nanocomposite labelled as ZQT was prepared via the sol-gel assisted hydrothermal method. The powder X-ray diffraction (XRD) analysis indicates that the average crystallite size of the ZnO QDs, anatase TiO2 (TiO2 NPs) and ZQT were 4.45 nm, 9.22 nm and 11.38 nm, respectively. Photoluminescent (PL) analysis detected the presence of defects related to TiO2, oxygen vacancies and quantum confinement effect (QCE) of the ZnO QDs in ZQT. These features enhanced the photodegradation of tetracycline (TC) under 48 watt of fluorescent light irradiation when ZQT (98.0%) was used compared to TiO2NPs (32.4%) and ZnO QDs (68.8%). The photodegradation activity was driven by O2●− followed by ●OH and h+.

Stone Mastic Asphalt (SMA) is a gap-graded hot mix asphalt that contains a large percentage of course aggregate and bitumen filler mastic. SMA is suffered from severe binder drain down due to the gap graded aggregates mixtures. Large difference between the sizes of aggregate tend to reduce tensile strength of the asphalt mixture. To overcome this, a type of fiber which is steel fiber is utilized to improve the tensile strength of SMA. Thus, the aim of this study is to increase the strength of SMA by utilizing steel fiber. To prepare SMA mixtures, specimens were compacted by applying 50 blows on each face using Marshall Compactor. Then, the modified specimens were tested to investigate the performance in terms of Los Angeles Abrasion Test, Marshall Stability Test, Resilient Modulus Test, and Dynamic Creep. From the results, it indicates that the addition of 0.3% fiber leads to better stability and stiffness while 0.5% fiber for resilient and enhanced modulus dynamic creep at 25°C and 0.4% fiber at 40°C. Thus, it can be concluded that the addition of steel fiber in the mixture significantly enhance the overall performance of SMA.

Porous Asphalt (PA) is known as a highly permeable asphalt surface that design to be permeable pavements for stormwater control and reduce the stormwater runoff. However, the structure is subjected to damage from cracking, rutting, stripping, and rapid aging under the effects of repeated vehicle loading, hot climates, and heavy rainfall. To overcome this, PA needs to modify using high tensile strength like steel fiber. Thus, this study aims to evaluate the performance of PA with the addition of steel fiber and overcome the issue that is related to PA. A mixture contains varying percentages of steel fiber were assessed to check which samples gives the best performance as per the requirement by using laboratory tests which are LA Abrasion, Resilient Modulus, Marshall Stability, and Density. The results show that the additions of 0.6% steel fiber give the lowest value of abrasion, while 0.5% fiber content contributes the highest value of Resilient Modulus and Marshall Stability respectively. PA mixtures modified with steel fiber produce the performance enhancement of PA as a road surfacing material. It is concluded that the asphalt mixtures containing steel fibers could increase the stability and strength of the mix.

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Stone Mastic Asphalt (SMA) is designed to improve durability and life span of road pavement through the use of a stable stone-on-stone skeleton held together by a rich mixture of asphalt. However, over time the structure is subjected to damage from cracking, rutting, stripping and rapid aging under the effects of repeated vehicle loading, hot climates and heavy rainfall. Previous studies proved that eggshell is capable to enhance the strength and durability of concrete. Thus, the aim of this study is to evaluate the performance of these stone mastic asphalt mixtures with the eggshell powder and overcome the issue that is related to SMA. A mixture contains varying percentages of eggshell powder were assessed to check which samples gives the best performance as per the requirement by using laboratory tests which are LA Abrasion and volumetric properties. Results indicated that eggshell powder can effectively recover and enhance abrasion resistance of asphalt and increases the marshal stability of SMA. SMA mixtures modified with eggshell powder produce the performance enhancement of SMA as a road surfacing material. It is concluded that the asphalt mixtures containing eggshell powder could be increases the stability and strength of the mix.