DEPARTMENT OF CIVIL ENGINEERING

The behaviour of shallow foundations constructed on lateritic soils is of significant importance in tropical regions where these soils occur extensively and are commonly used for civil engineering works. Lateritic soils are highly variable in nature, and their engineering performance is strongly influenced by factors such as mineral composition, moisture content, degree of compaction, and environmental conditions. This variability often leads to challenges in predicting foundation performance and ensuring structural safety. This study investigates the behaviour of shallow foundations on lateritic soils through a combination of field and laboratory investigations. Field studies include soil sampling an in-situ tests to assess the natural state of the lateritic deposits. Laboratory tests are conducted to determine the index properties, compaction characteristics, shear strength parameters, and bearing capacity of the soils. Model and empirical methods are employed to evaluate the load-bearing capacity and settlement behaviour of shallow foundations under different soil conditions. The results of the study establish relationships between key soil properties—such as moisture content, density, plasticity, and strength—and the performance of shallow foundations. The findings provide valuable insight into the load-bearing behaviour of lateritic soils and highlight the importance of proper soil characterization in foundation design. The study aims to contribute to safer and more economical design practices for shallow foundations in lateritic soil environments, particularly in tropical regions.

Building collapse remains a persistent challenge in urban areas across Nigeria, with Benin City experiencing a notable frequency of structural failures. It is a devastating phenomenon that leads to the destruction and loss of property and lives This paper represents a study on the hierarchical assessment of the underlying factors causing building collapse in the city of Benin. Utilizing a multi-criteria decision-making approach, the research categorizes and ranks the causes based on expert interviews, field observations, and documented case studies. Key factor examined include poor construction practices, substandard materials, inadequate regulatory enforcement, design flaws, and environmental influences. The hierarchical assessment process employs the use of structured questionnaire to gather data from professionals in the construction industry and ranks these causes based on the most voted factors into primary, secondary and tertiary factors revealing poor construction materials, inadequate supervision and regulation, corruption, poor workmanship and repurposing of buildings to be the most primary factors. Lack of proper engineering design, overloading, poor foundation work, weak enforcement of building codes and member failure to be secondary factors. Negligence and lack of maintenance, rapid urbanization and natural disasters to be tertiary factors. Recommendations to curb or reduce the issue of building collapse in the city of Benin are strict enforcement of building codes and regulations, quality control and material testing, enhanced professional training and certification, combating corruption, public awareness campaign, urban planning and zoning regulation, promotion of preventive maintenance, establishment of a building collapse response task force, encouraging use of technology in construction.

The increasing reliance on sachet water as a primary source of drinking water among students in
Ekosodin underscores the need for rigorous quality assessment. This study investigates the physicochemical and microbiological characteristics of various sachet water brands consumed in the region. Parameters such as pH, turbidity, total dissolved solids (TDS), and the presence of microbial contaminants were analyzed using standard laboratory techniques. The study aims to determine compliance with regulatory standards and assess potential health
risks associated with these products.

Water-logged soils are a persistent challenge in geotechnical engineering, especially in tropical regions where high rainfall and poor drainage lead to saturated ground conditions. These soils typically exhibit low shear strength, high compressibility, and poor load-bearing capacity, making them unsuitable for construction without prior treatment. In this study, bamboo ash, especially bamboo leaf ash (BLA), was assessed for its ability in improving soil strength, reducing permeability, and enhancing durability. Soil samples were collected from water-logged areas and classified using standard geotechnical tests. These soils fell under the category of high-plasticity clays or silts, which are prone to swelling, shrinkage, and settlement. Bamboo leaves were collected from a local source market. The bamboo ash was mixed with soil in varying proportions of 2%, 4%, 6%, 8%, and 10% by weight. The mixture was thoroughly blended and compacted using standard procedures. Tests that were carried out include Atterberg Limits test to assess changes in plasticity and consistency; compaction tests to determine optimum moisture content (OMC) and maximum dry density (MDD); and California Bearing Ratio to evaluate load-bearing capacity. The results showed that bamboo ash significantly increases shear strength, especially at an optimal content of around 4% to 6%; the plasticity index decreases, indicating better dimensional stability and reduced swelling/shrinkage behavior; and CBR values improved, making the soil more suitable for subgrade and foundation applications.

This study aims to investigate the potential of using pulverized glass as a partial substitute for fine aggregate in concrete, focusing on how it affects the mechanical properties of the resulting composite. By exploring various replacement levels of pulverized glass, the project identified an optimal balance that enhances both the sustainability and performance of concrete. An experimental work was performed to study the slump, unit weight, compressive strength, dry density and water absorption of concrete partially substituted with pulverized glass. A concrete mix with a target mean strength of 20N/mm² was designed using a standard 1:2:4 mix ratio. Pulverized glass was used to partially replace the fine aggregate at replacement percentages of 0%, 5%, 10%, and 15% in accordance to relevant literature. The concrete was then cast into cubes and allowed to cure for 7, 14, and 28 days at room temperature in a laboratory. The results indicate that workability increases with higher pulverized glass content, with slump values rising from 30 mm for the control mix to 46 mm at 15% replacement. However, compressive strength generally decreased as the replacement percentage increased. The 5% replacement mix achieved the highest compressive strength among the modified mixes, with an average 28-day strength of 19.72 N/mm² compared to 20.68 N/mm² for the control mix. Nine concrete mixes were examined using discarded glass in place of 0%, 5%, and 15% of the weight of sand. The study concludes that, crushed glass can substitute up to 5% of fine aggregate in concrete, which helps lessen the effects of sand mining. This concrete can be regarded as eco-friendly since it uses less raw materials and has fewer negative environmental effects.

Water-logged soils are a persistent challenge in geotechnical engineering, especially in tropical regions where high rainfall and poor drainage lead to saturated ground conditions. These soils typically exhibit low shear strength, high compressibility, and Poor loadbearing capacity, making them unsuitable for construction without prior treatment. In this study bamboo ash especially bamboo leaf ash (BLA) was assessed for its ability in improving soil strength, reducing permeability, and enhancing durability. Soil samples were collected from water-logged areas and classified using standard geotechnical tests. These soils fell under the category of high-plasticity clays or silts, which are prone to swelling, shrinkage, and settlement. Bamboo leaves were collected from a local source market. The bamboo ash was mixed with soil in varying proportions 2%, 4%, 6%, 8%, and 10% by weight. The mixture was thoroughly blended and compacted using standard procedures. Test that were carried out include; Atterberg Limits test to assess changes in plasticity and consistency; Compaction; tests to determine optimum moisture content (OMC) and maximum dry density (MDD); California Bearing Ratio (CBR) to evaluate load-bearing capacity. The results showed that bamboo ash significantly increases shear strength,especially at an optimal content of around 4% to 6%, The plasticity index decreases, indicating better dimensional stability and reduced swelling/shrinkage behavior; CBR values improved, making the soil more suitable for subgrade and foundation applications.

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.

Climate change poses significant threats to the built environment through rising temperatures, altered precipitation patterns, and increased frequency of extreme weather events. This study investigated the impact of climate change on the durability of building materials commonly used in Nigeria. A comprehensive analysis of 60 years of meteorological data (1965-2024) from the Nigerian Meteorological Agency (NIMET) was conducted across Nigeria's three climatic zones. The data was divided into two 30-year periods Historical Period 1 (HP1: 1965-1994) and Historical Period 2 (HP2: 1995-2024) to identify climatic trends and their implications for concrete, steel, timber, and masonry materials. The methodology employed secondary data collection and literature review, analyzing four key climatic parameters: mean annual temperature, total annual rainfall, mean annual sunshine hours, and mean annual wind speed. Comparative analysis revealed significant environmental shifts, with Southern Nigeria experiencing the most severe changes including temperature increases of +1.0°C, rainfall increases of +298mm, and reductions in both sunshine hours (-0.6 hr/day) and wind speed (-0.6 m/s).Results demonstrated that all building materials face substantially accelerated degradation under current conditions. Concrete experiences enhanced carbonation and chloride penetration with 2030% service life reductions. Steel reinforcement shows 30-40% service life reduction in coastal environments due to intensified corrosion. Timber faces the highest vulnerability with potential 40-50% service life reductions from enhanced fungal decay and increased termite activity. Porous masonry units experience severe efflorescence and progressive strength loss, resulting in 20-40% service life reductions. The study revealed synergistic effects where combined climatic changes produce deterioration exceeding individual impacts, with Southern Nigeria facing the most aggressive conditions. The study concludes that traditional construction practices based on historical climate data are inadequate for current conditions. Recommendations include immediate revision of building codes and material specifications, adoption of climate-resilient materials and enhanced protective systems, implementation of climate-responsive design approaches, and intensified maintenance programs for existing structures. These findings provide critical insights for stakeholders to enhance building resilience and ensure the sustainability and safety of Nigeria's built environment.

This study assessed the water quality of the fish pond located at the Faculty of Agriculture, University of Benin, with the aim of determining its Water Quality Index (WQI) and proposing environmentally sustainable alternative uses in the event of water exchange or discharge. The study was carried out in response to the growing need for scientific evaluation of aquaculture effluents, which, if improperly managed, may cause ecological degradation through nutrient enrichment, heavy metal buildup, and microbial contamination. The research therefore sought to evaluate the physicochemical and microbial characteristics of the pond water, compute its WQI using the Arithmetic Weightage Index Model, and recommend safe reuse or disposal options. Water samples were collected from two ponds (Sample A and Sample B) representing five-day and thirteen-day retention periods respectively. Laboratory analyses were performed in the Civil Engineering Hydraulics/Water Laboratory following APHA (2017) standard methods to determine parameters such as pH, turbidity, total dissolved solids (TDS), total suspended solids (TSS), etc. The obtained data were analyzed using the Arithmetic Weightage Index Model, where individual parameter values were compared against WHO (2017) and FAO (2011) standards to derive the overall WQI and corresponding water quality grades The results showed that Sample A, with a WQI of 20.41, was classified as Excellent, indicating that the pond water met acceptable limits. Sample B, with a WQI of 51.69, fell under the Poor category, signifying moderate pollution resulting from prolonged water retention, organic enrichment, and higher microbial counts. Consequently, while Sample A water could be reused or safely discharged without treatment, Sample B water required simple treatment such as aeration or sedimentation prior to reuse or discharge. The study concluded that proper monitoring of water quality and periodic application of the WQI approach are vital for sustainable aquaculture management. It recommended regular effluent testing, adoption of low cost pre-treatment systems, and reuse of treated pond water for agricultural irrigation or secondary aquaculture to reduce environmental pollution and promote resource conservation.

The project addresses the growing concern of gully erosion in regions like Benin City, Nigeria, where intense rainfall and poor land management have caused severe soil degradation, loss of agricultural land, and infrastructure damage. Traditional erosion control methods have often been costly, rigid, and unsustainable. This study introduces gabion retaining structures as a flexible, cost-effective, and environmentally friendly alternative. Gabions, which are wire mesh baskets filled with stones, offer the ability to withstand flowing water and adapt to unstable ground while promoting soil stability and water conservation. The study involves evaluating the performance of gabion structures in mitigating gully erosion in a specific location Federal College Road, Benin City. Site reconnaissance to identify critical erosion-prone areas was done. Hydrological analysis using the Rational Formula estimate streamflow was carried out whilst designing, assembling, and installation of gabion baskets in affected zone was done with key design considerations including appropriate stone size, mesh type (Type 60: 60×80 mm), and structural layout. The performance of the gabions was assessed through regular visual inspections for deformation and settlement. The project demonstrated that gabion structures are a sustainable and practical solution for controlling minor gully erosion. Results showed improved soil stability and there was a clear reduction in both the depth and speed of water flow from 0.71 m to 0.52 m in depth and from1.54 m/s to 1.39 m/s in speed helping to stabilize the gully and prevent further soil loss. Additionally, the structure was able to withstand environmental stresses without major maintenance, offering a scalable model for other erosion-prone regions. This result provides useful insights for engineers, policymakers, and local communities seeking cost-effective solutions for land protection and sustainable infrastructure.