Permeable pavement is an environmentally beneficial material that can ease urban problems and mitigate the effects of climate change, such as flooding, urban heat islands, and groundwater decrease. However, it is susceptible to clogging, has limited strength, and demands frequent maintenance. To overcome these problems, an untraditional fiber-reinforced permeable pavement with a low tortuosity pore structure that has an excellent infiltration rate and strength while being resistant to clogging has been studied in this research. Straight pore channels of various sizes and quantities were introduced into self-compacting concrete to create this permeable pavement. High-strength pervious pavement (HSP) samples with porosity ranging from 3.60 to 8.30% and 0–0.2% fiber content were tested. In all cases, HSP showed high infiltration rate (>1 cm/s), high compressive strength (>27 MPa) and tensile strength (1.5 MPa), low mass loss in potential resistance to degradation by impact and abrasion (>25%). However, it did not clog despite extensive cyclic exposure to flow containing sand, clay, and combined ‘sand & clay’. PP fiber content of 0.1%. The 3.60% porosity was found to be optimum considering all properties, whereas 8.30% porosity gave a higher infiltration rate with compromised properties. This permeable pavement can maintain sufficient porosity and permeability for stormwater infiltration without frequent maintenance. Adding polypropylene fiber reduces compressive strength marginally but increases split tensile strength, degradation and potential resistance. This novel fiber-reinforced HSP has the potential to expand the material's applicability. The results obtained from this research are expected to lead the way for a broader application of HSP in various contexts and initiatives that were not previously considered appropriate. This will eventually enhance the design and implementation of a new generation of flood-resistant infrastructure and significantly improve the ability to mitigate urban floods.

The pursuit of sustainable and eco-friendly materials has fuelled research into enhancing composite materials using bio fillers derived from renewable sources. This study investigates the incorporation of bio filler - biochar produced from cashew nut shell, in hemp fibre composite to achieve a balance between performance and environmental sustainability. Hemp fibre composites were fabricated with four different weight percentages of biochar such as 5, 10, 15, and 20 wt%. Hemp fibre composites with biochar showed enhanced mechanical strength and water resistance when compared to composite without biochar. The composites containing 10 wt% biochar added showed the maximum tensile, impact, and hardness, ca. 94%, ca. 38%, and ca. 7% increase compared to composite without biochar, respectively. The highest flexural strength (ca. 71 MPa) was observed at a biochar addition of 15 wt%. The integration of biochar improved the filler-matrix interaction by enhancing adhesion, creating effective stress transfer within the vinyl ester matrix, thereby reinforcing the composite's structural integrity. In the water absorption test, the biochar acted as barrier to the water molecules and reduced the water absorption by ca. 32–63%. These findings highlight the potential of biochar-based fillers in advancing the field of composite materials, providing a more nuanced understanding of their applications in addressing both environmental concerns and bio waste accumulation.

In vehicles powered by fuel, the effort to minimize CO and HC emissions through various strategies leads to an increase in CO2, contributing to global warming. This study aimed to experimentally assess the simultaneous reduction of vehicle tailpipe emissions of CO, HC, and CO2 using desirability function analysis (DFA). On predetermined routes in Addis Ababa city, two vehicles were tested for on-road emissions at five various speeds and on five various road slopes using a portable emissions tester. Surface plots were used to display how the tailpipe emissions of CO2, CO, and HC vary with changes in vehicle speed and road gradient. The DFA results revealed that the optimal speed for simultaneous reduction of CO, HC, and CO2 emissions was 40 km/h on a flat route and 30 km/h on a 2-degree uphill, with composite desirability of 0.83 and 0.72, respectively. This study found that a speed of 30 km/h on a flat road increased CO2 by 2.82%, CO by 18.97%, and HC by 5.28% compared to an optimized vehicle speed of 40 km/h. On a 2-degree gradient, a vehicle traveling at 20 km/h exhibited a 4% increase in CO2 emissions, a 23.92% increase in CO emissions, and a 1.26% decrease in HC emissions compared to the optimized speed of 30 km/h. Adjusting speed limits according to road gradients is recommended to minimize vehicle tailpipe emissions simultaneously using DFA. This approach contributes to lowering air pollution by reducing pollutant emissions from vehicles through optimized speeds.