In the heart of Nigeria, a groundbreaking study is turning the humble periwinkle shell into a potential game-changer for road construction. Salisu Yusuf, a civil engineering researcher from Bayero University in Kano State, has been exploring the use of Periwinkle Shell Ash (PSA) to enhance the geotechnical properties of lateritic soil, a common material used in road construction. The findings, published in ‘Platform, a Journal of Engineering’ (which translates to ‘Podium, a Journal of Engineering’ in English), could have significant implications for the construction industry, particularly in regions where lateritic soils are prevalent.
Yusuf’s research focuses on the potential of PSA to improve the load-bearing capacity and strength of lateritic soil, making it a more viable option for road construction. “The idea was to find a locally available and sustainable material that could enhance the properties of lateritic soil,” Yusuf explained. “Periwinkle shells are abundant in coastal regions, and turning them into ash could provide a useful byproduct for construction.”
The study involved mixing lateritic soil with varying percentages of PSA, ranging from 0% to 10%. The results were promising. The addition of PSA led to a reduction in the liquid limit of the soil, indicating a decrease in its plasticity and an increase in its stability. The plastic limit increased, suggesting that the soil becomes less plastic and more stable upon the addition of PSA. The Maximum Dry Density (MDD) of the soil also improved, while the Optimum Moisture Content (OMC) decreased, which is beneficial for road construction as it indicates that the soil can withstand more load with less moisture.
One of the most significant findings was the improvement in the soil’s California Bearing Ratio (CBR) and Unconfined Compressive Strength (UCS). The CBR, a measure of the soil’s load-bearing capacity, increased from 26% to a peak value of 40%. The UCS, which indicates the soil’s strength, also saw a substantial increase, reaching up to 215 kN/m2 after 28 days of curing. These improvements were achieved at an optimized PSA content of 8%, which met the Nigerian General Specifications for Roads and Bridges (2016) criteria for sub-base materials.
The commercial impacts of this research could be substantial. For the energy sector, which often requires extensive road infrastructure for transportation and logistics, the use of PSA could provide a cost-effective and sustainable solution. It could also reduce the dependency on imported materials, thereby lowering costs and promoting local industries.
“This research opens up new possibilities for sustainable construction practices,” Yusuf noted. “It’s not just about improving the soil’s properties; it’s about finding innovative ways to use local resources and reduce waste.”
The study’s findings could pave the way for further research into the use of agricultural and marine byproducts in construction. It also highlights the potential of local materials in addressing global challenges in infrastructure development. As the world seeks more sustainable and cost-effective solutions, research like Yusuf’s could play a crucial role in shaping the future of the construction industry.
In the meantime, the construction industry in Nigeria and beyond is watching closely. The use of PSA could be a step towards more sustainable and resilient infrastructure, benefiting not just the construction sector but also the environment and local economies. As Yusuf’s research continues to gain traction, it’s clear that the humble periwinkle shell might just hold the key to building stronger, more sustainable roads.