CIVIL ENGINEERING

This project examined the environmental and health hazards from the disposal of liquid waste generated by industries, particularly those involved in beverage production in Nigeria. Increased urbanization and rapid industrialization have occasioned increased volumes of effluent being discharged, usually without proper treatment, into River Niger and other water bodies. This results in various forms of pollution, contaminating the organic and inorganic content, ultimately causing about 25% of all preventable diseases, including waterborne diseases. This research work aimed to study and upgrade the liquid waste disposal methods at the International Breweries Limited Onitsha, Anambra State. Specific objectives included establishing the physical, chemical, and biological characteristics of the effluent and also appraising the sustainability and efficiency of the existing effluent treatment and disposal processes with respect to compliance with WHO standards. The methodology used in this research involves a case study approach at the brewery plant. Effluent samples were collected from pre-treatment and post-treatment points during the month of August, at morning periods to capture peak production waste. Each sample size was 2 liters, preserved at 4°C, and conveyed to the laboratory within 4 hours. Physical parameters such as pH, temperature, turbidity, total suspended solids, and color were analyzed using calibrated instruments like pH meters and spectrophotometers. Chemical parameters for biochemical oxygen demand, chemical oxygen demand, heavy metals, and nutrients were analyzed by digestion followed by atomic absorption spectrophotometry. Biological parameters-total heterotrophic bacteria, coliform counts, and E. coli-were determined by membrane filtration and incubation on selective media. Data analysis involved the use of descriptive statistics and comparison with WHO benchmarks. These results portrayed partial efficacy of the treatment. Physical parameters were improved, with turbidity falling from 1.0 NTU to 0.5 NTU; however, pH and total dissolved solids were still above WHO limits at 5.0 and 2829 mg/L, respectively. The chemical parameters were reduced-for instance, COD was reduced from 80.1 mg/L to 56.3 mg/L-but remained high, as were heavy metals (e.g., lead, 0.74 mg/L> 0.01 mg/L) and nutrients (ammonia, 8.74 mg/L> 0.5 mg/L); thus, offering a high risk for eutrophication and toxicity. Biological parameters were fully met, as coliform and E. coli counts were nil after treatment. The study concluded that the brewery's treatment system was inefficient to achieve full compliance, with the need to invest in effective treatment technologies such as reverse osmosis and nutrient removal. Individuals should advocate for clean water practices, corporate organizations should invest in advanced treatment technologies, and
government agencies should establish stricter monitoring and incentives for sustainable waste management.

The behavior 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 and 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 behavior 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 behavior 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.

The study addressed the critical challenge of ensuring safe and sustainable borehole water quality in the University of Benin, Benin City, Edo Satae, Nigeria, where contamination risks from anthropogenic and environmental factors threaten public health. The study aimed to assess spatial variations in borehole water quality, evaluate compliance with national and international standards such as the NSDWQ and WHO standard and visualize contamination risk zones using GIS techniques.
Geographic coordinates were obtained using a GPS navigation tool called coordinate and water samples for laboratory analysis were collected at three borehole sites: A, B and C and their respective distribution points. Thirty-four physicochemical and microbial parameters were analyzed in accordance with the APHA standard laboratory procedures. The Weighted Arithmetic Water Quality Index (WAWQI) method was applied to compute the WQI for each sampling point. The results were integrated into ArcGIS Pro software, where shapefiles were created and thematic maps generated to show spatial distribution of WQI and individual parameters relative to environmental features such as septic tanks and drainage channels. The results of the pH, electrical conductivity, turbidity, total dissolved solids, values ranged from 4.8 to 6.0, 110 to 305 µS/cm, 3.48 to 4.04 NTU and 56 to 153 mg/L respectively. Calcium and Magnesium ranged from 2.87 to 7.14 mg/L and 1.61 to 4.00 mg/L respectively corroborating the low hardness values of 13.8 to 37.6 mg/L.
Concentrations of iron, manganese, zinc, copper ranged from 0.210 to 0.327 mg/L, 0.045 to 0.070 mg/L, 0.107 to 0.167 mg/L and 0.017 to 0.026 mg/L respectively. Microbiological results revealed that total heterotrophic bacterial counts were present in Borehole B and distribution points A and C at 10 × 10³ CFU/mL, all samples tested negative for coliforms and E. coli, indicating the absence of fecal contamination. Boreholes points A and B had WQI values of 61.27 and 57.30, inferring good quality, while Borehole C, distribution points A, B and C exhibited higher WQI values of 73.94, 82.79, 79.64 and 98.80 respectively reflecting post-storage contamination and influence from surrounding activities having a water quality grade of poor in line with the WHO and NSDWQ standards. The study concluded that GIS proved highly effective in visualizing spatial water quality variations and identifying areas at risk of contamination.

This study assesses the efficiency of activated carbon in treating copper nitrate contaminated borehole water for domestic and irrigation purposes. The increasing contamination of groundwater by heavy metals and nitrates poses serious environmental and public health concerns, particularly in developing regions. The aim of this research was to evaluate the ability of activated carbon to reduce copper and nitrate concentrations in borehole water and to determine its suitability for sustainable water reuse. Borehole water samples contaminated with copper ions (Cu²⁺) and nitrate were treated with activated carbon at different contact times under laboratory conditions. Physicochemical parameters such as pH, electrical conductivity, turbidity, copper concentration, and nitrate concentration were analyzed before and after treatment using standard laboratory methods. Adsorption behavior was evaluated using Langmuir and Freundlich isotherm models, while adsorption kinetics were investigated using pseudo-first-order and pseudo-second-order kinetic models to understand the mechanism of adsorption. The results showed a significant reduction in copper and nitrate concentrations after treatment with activated carbon. The Langmuir isotherm model showed the best fit with correlation coefficients (R²) of 0.9949 for copper and 0.9861 for nitrate, indicating monolayer adsorption on a homogeneous surface. The Freundlich model also showed good correlations (R² = 0.9500 for copper and 0.9624 for nitrate). Kinetic analysis revealed that the pseudo-second- order model better described the adsorption process, with R² values of 0.9824 for copper and 0.8049 for nitrate. The treated water quality improved and was suitable for irrigation and moderately improved for domestic use, confirming that activated carbon is an effective and low-cost adsorbent for reducing copper nitrate contamination in borehole water

This research project studied on how organic waste generated domestically can be converted into compost. Organic wastes are wastes which are generated from plants, animals or micro organisms, which can be broken down. The aim of this research project was to produce compost by utilizing domestic wastes collected from selected households in BDPA, Benin City within a duration of 4 weeks by determining the average waste generated from the respective households and how much compost can be generated from the organic wastes, by studying the biology of the composting process and identifying the impacts of composting in the environment. There are many approaches to studying compost. During this research study, the aerobic composting method was adopted and in so doing, the organic wastes were sorted from the domestic wastes collected from the various households and decomposed using microorganisms that require oxygen. These organic wastes generated consisted of spoiled/perishable foods, bones, vegetables/leaves and woods. The results from this research showed that after four weeks of composting, the total wastes obtained were 30.02kg, 27.56kg, 35.25kg and 31.63kg while the total compost obtained from the respective houses were 8.6kg, 8.8kg, 12.6kg and 8.6kg. These results revealed that the compost generated were about one-third of the total domestic waste collected originally. The percentages of organic waste produced per week were determined to be 63.29%, 68.21%, 72.05% and 69.55%. Domestic wastes could cause problems in the environment if not well managed and utilized for good. Composting is the best low-cost alternative to solve this problem simply because composting can degrade all types of organic wastes, such as fruits, vegetables, herbs, plants, yard wastes and others. The product from the decayed organic waste in the form of compost could be used as nutrients for crops, soil additives and for environmental management. However, factors such as pH of the pile, temperature of the pile, moisture content off the compost pile and concentration of carbon and nitrogen in the organic material and aeration are some of the main parameters which contribute to 9 9 9 112 vi the efficiency of the composting process. The study of composting is an important part of the global strategy for the collection, treatment and disposal of domestic waste as it also identifies the benefits of composting and the positive effect it would have in the environment.

This project is conducted to carry out a comparative study of the deflection characteristics of Prestressed geopolymer concrete and Prestressed Portland cement concrete. The objectives are to conduct tests on the materials utilized, to carry out flexural tests and other supporting tests and to analyze the results obtained from all the tests performed. The aim of the research is to
compare the deflection characteristics of Portland Cement beams and Metakaolin based Geopolymer concrete beams. The tests performed on the materials utilized were the sieve analysis test on aggregates, specific gravity test on the kaolin, metakaolin,
cement and aggregates, and the tensile test on
cables, tendons and wires. The other supporting tests done were the compressive strength test of Portland Cement concrete and geopolymer concrete, and workability test on concrete. The preliminary test proved that the calcined metakaolin samples were reactive when exposed to alkaline activators and metakaolin based geopolymer concrete exceeded the strength of ordinary Portland cement concrete in short time. The compressive strength of the 8 molarity metakaolin based geopolymer concrete was gotten as 38.267 N/mm2 after 1 day; after 5 days, it was gotten as 51.510 N/mm2; after 7 days, it was gotten as 52.651 N/mm2, and after 28 days, it was gotten as 57.950 N/mm2. The compressive strength of the 10 molarity metakaolin based geopolymer concrete was gotten as 29.262 N/mm2 after 1 day, and after 7 days, it was gotten as 38.730 N/mm2. The average moment
capacity of the geopolymer concrete beams prepared from 8 molarity of NaOH was gotten 482.36 Nm. The moment capacity range of the geopolymer concrete beams prepared from 10 molarity of NaOH was gotten as 338.0 – 349.5 N/mm2.

Pollution is a very predominant problem in Nigeria. As a developing nation, we face
challenges of constant economic recession and this can have effect on so many facets of life
including construction. Road construction is now so expensive. In other to combat pollution
and bad roads, waste can be used with other construction materials to construct better
roads.
In this study, the geotechnical properties of natural soil were determined, the effect of
mixture of orange peels in proportions of 2%, 4%, 6% and 8% were observed and the
appropriate mix ratio was ascertained. The soil samples were obtained from Faculty of
Engineering, University of Benin, Benin City, Edo State, from two locations. The following
tests were carried out; Moisture content Test, Specific Gravity Test, Sieve analysis, Atterberg
Limit tests, Compaction tests, California Bearing Ratio tests and on the treated and
untreated laterite soil. This laboratory tests were carried out to determine the suitability of
these waste materials when mixed with the soil samples. For the control sample, the specific gravity was obtained to be 2.69 and 2.73 which is above
2.50 but not greater than 3.0 for lateritic soils, this shows a high plasticity. The plasticity
index was obtained as 39.49% which indicates that the soil is not medium in plasticity. Also, from the sieve analysis, the soil is classified as an A-2-6 soil according to AASTHO. This value
indicates that it is good for subgrade material. Therefore, these soil reinforcement
techniques with orange peel can only be used for Trunk D roads or as subgrade materials
which require a minimum soaked CBR of 5%. For Trunk A, B and C roads, the mixture would
require a binder like cement before being considered as subbase and base course materials