R.I. Umasabor

This research investigated the utilization of polypropylene (PP) waste as an additive in the production of sandcrete blocks, aimed at promoting sustainable waste management and reducing the environmental impact of plastic pollution. The study sought to determine the influence of varying polypropylene waste contents on the physical and mechanical properties of sandcrete blocks, thereby evaluating its suitability as a construction material modifier. The experimental work involved producing paving stone specimens with 0%, 1%, 2%, 3% and 4% polypropylene waste by weight of sand. Aggregates were first characterized through specific gravity and sieve analysis to ensure conformity with standard specifications. Sandcrete blocks were then cast, cured in water, and tested for water absorption and compressive strength at 3 and 7 days of curing, following procedures outlined in relevant British Standards. This methodology ensured uniformity in mixing, curing and testing, allowing a clear assessment of polypropylene’s effect on the samples’ performance. The results showed the polypropylene addition influenced both durability and strength properties. Water absorption ranged between 0.64% and 2.88% with the lowest value recorded at 4% PP content, suggesting improved impermeability at higher plastic dosages. Compressive strength ranged from 11.41Mpa and 16.07Mpa, with optimum strength achieved at 1% PP addition, after which a gradual reduction is observed. It was concluded that the inclusion of polypropylene waste up to 1% can enhance strength and durability without compromising structural performance. The study recommends using low dosages of polypropylene waste in sandcrete blocks production and encourages further research into improving interfacial bonding through surface modification and longer curing periods to
maximize the material’s potential for sustainable construction.

Concrete is one of the most widely used construction materials in Nigeria due to its strength, durability, and versatility. However, the increasing cost of granite and the environmental impact of quarrying have created the need for alternative, sustainable materials. At the same time, palm kernel shell (PKS), a by-product of palm oil processing, is generated in large quantities and often disposed of as waste, leading to environmental pollution. This study investigates the suitability of palm kernel shell as a partial replacement for granite in Grade 20 concrete. Granite was partially replaced with PKS at 0%, 10%, 20%, and 30% by weight. The physical properties of PKS, including specific gravity, bulk density, and aggregate impact value, were
determined. Concrete mixes were produced and tested for workability using the slump test, as well as fresh and hardened density. Concrete cube specimens were cast and cured for 7, 14, and 28 days before compressive strength testing in accordance with relevant British Standards The results indicated that the incorporation of PKS reduced the density of concrete, confirming
its potential for lightweight applications. Workability and compressive strength decreased with increasing PKS content due to the high water absorption and lower strength of PKS compared to granite. However, concrete containing up to 20% PKS achieved compressive strength values close to the target strength for Grade 20 concrete at 28 days. It was concluded that palm kernel shell can be used as a partial replacement for granite up to an optimum level of 20%, offering a cost-effective and environmentally friendly alternative for sustainable concrete production