DEPARTMENT OF CIVIL ENGINEERING

Flood frequency analysis is the most important statistical technique in understanding the nature and magnitude of high discharge in a river. The objective of frequency analysis is to relate the magnitude of events to their frequency of occurrence through probability distribution. The various methods used in the estimation of design flood as a criterion for the design and construction of hydraulic structures which in most countries is undermined during the planning of such infrastructure thereby causing significant damages and loss of lifes and properties. Log Pearson type III distribution model and Gumbel probability along side with three plotting position s of Weibull, Gringorten and Cunnane was used. The Gumbel probability distribution and Log Pearson type III distribution values were similar

The essence of traffic volume count in any society cannot be overemphasized. The importance varies from city to city depending on its level of development and the projected level of safe and efficient traffic management it aims at attaining within a stipulated time. This study has reviewed and highlighted and discussed the causes, general effects and possible solutions to the regular traffic congestions on the University of Benin Teaching Hospitals Junction which has become a norm for decades. The study employed simply method of manual traffic count in obtaining the data required for the study. A set of questionnaires with few relevant questions concerning the management oftraffic on the junction was equally administered on the drivers who ply the junction within the period of the study. Tally system of bundle and strokes were used in the study for easy documentation of the volume of the traffic being counted. The study has reviewed the major causes of traffic congestion on the junction to include in adequate parking space, low carrying capacity of the junction as compare to the expected traffic, poor traffic management, lack of basic traffic facilities and personnel, poor implementation of traffic rules and regulations and disobedience to traffic orders and wardens. It has also suggested some of the remedies to include construction of standard interchange structures such as overhead bridge and flyover on the junction, stiffer measures on the traffic offenders, implementation of traffic policies and periodic traffic study on the junction and installation of traffic facilities on the junction to ensure smoother flow of traffic considering the strategic importance of the intersection to the socio-economic well-being of the Benin-City, Edo State and Nigeria in general

This research investigates the structural behavior of a reinforced concrete box culvert under variable hydraulic conditions typical of urban drainage systems in Benin City. The study addresses the problem of culvert deterioration caused by internal sedimentation, foundation scour and variable headwater levels. The aim of the research was to develop a data-driven model that links observable hydraulic conditions to quantifiable structural responses, thereby improving performance evaluation and maintenance prioritization.To achieve this, field investigations were conducted at the Ogba River drainage corridor to determine practical ranges for the three hydraulic variables. Response Surface Methodology (RSM) was employed to generate a design matrix with 20 experimental runs. Finite Element Analysis (FEA) was performed for each run to simulate the resulting wall shear force response. Six center points were observed in the matrix to ensure adequate degrees of freedom for estimating pure error and testing lack of fit in the ANOVA. The RSM model achieved a coefficient of determination (R²) of 98.6%, confirming the model’s high predictive accuracy. Results showed that the headwater level had the most significant effect on the wall shear force. The effect of the headwater level on the wall shear force is amplified by its interaction with foundation scour. Optimization analysis identified critical combinations of the variables that produced maximum WSF values greater than 70 kN/m, indicating the threshold beyond which the culvert’s structural integrity may be compromised. The developed model provides a quantitative framework for predicting wall shear forces based on measurable hydraulic conditions, offering a practical decision-support tool for culvert maintenance and management in resource-constrained urban environments such as Benin City.

Solid wastes constitute a disaster for human health and environmental degradation. Dumpsites in urban settlements are used as sources of nutrient rich soils for cultivating crops without regard to the risks of perceived toxic heavy metal pollution from the wastes. Water sources near the dumpsites are used as domestic water source for the people living near such sites. This water is often contaminated by toxic heavy metals leaching from the dumpsite. Heavy metals are known to accumulate in the plants then passed to the humans through the food chain. Prolonged consumption of unsafe concentrations of heavy metals through foodstuffs may lead to the accumulation of heavy metals in the humans causing disruption of numerous biochemical processes. The aim of this study was to determine the level of heavy metals in the vegetables and soil samples collected around Oluku dumpsite. The study also sought to assess the knowledge of the health risks posed by the site to the residents living around the dumpsite. Heavy metal determination samples collected was carried out using X- ray fluorescence (XRF) analytical method.
The results indicate that the dumpsite didn’t shown to be having high concentrations of heavy metals, since some heavy metals could not be detected in dumpsite. This may be as a result of less contamination with those metals due to human activities. Some metals could not be detected; the implication is that the concentration of these metals are below detection limit or not present at all. It was also observed that the dumpsite had higher concentration of these metals like magnesium (Mg) than others; this could be attributed to the presence of waste carrying higher amounts of magnesium. The heavy metals concentration in these dumpsites were all within the WHO acceptable limit in the dumpsite.

In Nigeria, road construction is often followed by neglect, with little or no provision for maintenance. This accelerates pavement deterioration due to factors such as rain fall, traffic loads, poor drainage, and harsh environmental conditions. This study aims to evaluate the condition of a 0.25 km road connecting Ethiope River Road and the University of Benin Back Gate (Ugbowo Campus). The study involved a field survey to document visible deterioration, followed by an assessment using the Pavement Condition Index (PCI) and Pavement Condition Rating (PCR) methods. The procedure adhered to ASTM D6433-07 standards, with the roadway divided into 5 sample units. Each unit was inspected for distress type, severity, and extent, and PCI values were calculated and categorized from “Failed” to “Excellent.” The results were analyzed and mapped using ArcGIS software for spatial visualization. The calculated PCI values for the five sample units, S1, S2, S3, S4 and S5 were 75, 49, 62, 55, and 32 respectively. These values correspond to pavement condition ratings (PCR) spanning from Satisfactory to Very Poor. The overall PCI for the road section was determined by computing the average of the individual unit PCI values, yielding an overall PCI of 54.6 for the Ekosodin Road, which classifies the pavement as being in a poor condition according to ASTM D6433-07 standards. The GIS-based spatial analysis revealed a concentration of severe pavement distresses toward the mid and lower portions of the road, suggesting localized structural and drainage-related problems. The results (Overall PCI of 54.6 and the digitized road section) indicates that while the pavement remains marginally serviceable, it requires urgent maintenance and partial rehabilitation to restore its functionality and prevent further deterioration. The combined use of PCI, PCR, and GIS tools proved to be a reliable and effective approach for comprehensive pavement condition assessment and should be adopted for routine pavement management within the University of Benin and similar environments

This study examined the use of Crushed Concrete as a soil stabilizer to enhance the geotechnical properties of weak subgrade soils for road construction projects. The growing volume of construction waste and the environmental issues linked to traditional stabilizers such as cement and lime were key motivations for this research. The soil sample was mixed with varying amounts of CC i.e. at 6%, 12% and 18%. Laboratory tests were conducted and they include sieve analysis, Atterberg limits, compaction and CBR tests. The results were analyzed graphically using Microsoft Excel. The particle-size analysis categorized both the natural soil and the crushed concrete as fine sand to fine gravel. The Atterberg limits indicated that as CC content increased, both the liquid limit and plasticity index decreased, suggesting reduced cohesion and better workability. Compaction results revealed that the maximum dry density (MDD) increased from 1.85 g/cm³ at 0% to 1.92 g/cm³ at 12% CDW, while the optimum moisture content (OMC) decreased from 13.52% to 12.00%, indicating an improvement in compaction efficiency and a reduction in water demand. CBR results also showed significant increases in both soaked and unsoaked values with higher CC concentrations, which met the standards of the Federal Ministry of Works and Housing (FMWH, 2016). In summary, this study found that crushed concrete is a potent and environmentally sustainable soil stabilizer that can significantly strengthen and stabilize weak subgrade soils. It demonstrated that using CC can serve as a viable alternative to conventional stabilizers, reducing construction costs while promoting waste recycling. Further research is recommended to investigate the long-term durability and field performance of CDW- stabilized soils under traffic loads.

The increasing number of abandoned buildings in developing countries highlights the pressing need for a credible means to determine the safety and soundness of reinforced concrete(RC) structures. This paper offers a forensic investigation of the RC beams in the abandoned commercial structure that halted construction because of suspected material strength and construction quality. To meet this challenge, this study provides a framework that combines non destructive testing (NDT) with computational modeling. The rebound method is a penetration test. It is a reliable method to determine the strength of damaged concrete. It is well suited to strength assessment of concrete near to the surface. It isaquick method and is particularly useful when drilling is not undertaken. It is accurate in comparison with other methods such as the Gill fall method. Rebound tests can be performed indepth. The rebound method measures the strength of concrete. It can determine the strength of concrete near to the surface. It is accurate to determine strength. It is relatively less accurate if the concrete is damaged. Moreover, the section cut-off method provides accurate results. It is carried out to determine strength. The method is well-suited to determine. The results showed large variations in the strength of the concrete for the beams, which is indicative of the varied standards of their construction and their less-than-full conformity to the nominal strength grade C30. Notwithstanding the above, it is apparent that there is potential within the results to satisfy the strength requirements of serviceability deflection. This lends support to the proposal to adopt a targeted repair strategy. Thus, this paper established that the combined usage of NDT and numerical models is a reliable and non-invasive method for assessing the status of deteriorated RC buildings. This method not only verifies the results attained through experiments done on the structure according to codes of practice but can also serve as a reliable guideline for future repair work.

This research was carried out to investigate the feasibility of using recycled waste glass as a partial replacement for coarse aggregate in concrete. The aim was to evaluate the mechanical,
physical and durability characteristics of concrete containing different proportions of crushed waste glass, thereby promoting sustainable construction practices. The methodology involved collecting, cleaning, crushing and sieving waste glass bottles into
particles of 10–20 mm in size. Five concrete mixes were prepared using a 1:2:4 mix ratio, with 0 %, 10 %, 20 %, 30 %, and 40 % waste glass as partial replacements for granite. All specimens were cured in water for 7, 14 and 28 days. Tests conducted included slump (for workability), compressive strength, density, setting time and water absorption capacity. The results showed that workability increased with higher waste glass content, with slump values ranging from 30mm for the control mix to 60mm at 40% replacement. The compressive strength of 30% replacement after 28 days was 20.30 Mpa, hence it was the optimum replacement level. The density of the concrete decreased slightly from 2.612g/cm3 (0%) to 2.391 g/cm3 (40%), indicating lighter concrete at higher glass content. The setting time test recorded an initial setting time of 65 minutes and a final setting time of 172 minutes, both within standard limits. Water absorption decreased from 1.6% at 0% replacement to 1.2% at 30%, showing improved durability and reduced porosity. From the findings, it was
concluded that waste glass could be used effectively as a partial replacement for coarse aggregate in concrete up to 20% without significant loss in strength or durability.

Electronic waste is an emerging issue posing serious pollution problems to human and the environment. The specific objectives of this work are to determine the physical properties of crushed e-waste materials, granite and aggregates, to design a concrete mix incorporating e-waste and granite as the coarse aggregate, to investigate the strength development of e-waste concrete at 7, 14 and 28 days, under standard curing method, to determine the effect of e-waste replacement on the compressive and flexural strength of concrete, and to analyse the result and ascertain the benefits of e- waste in the production of concrete. The research methodology will involve performing a comprehensive literature reviewand laboratory investigation of compressive strength and flexural test. Before that, several series of test would be carried out which includes specific gravity test, sieve analysis test, mix design, slump test, and casting of concrete test cubes. The results showed that adding e-waste as a partial replacement for coarse aggregate increased workability but reduced strength. Slump values rose from 27mm in the control mix to 61 mm at 20% replacement, indicating greater fluidity due to the smooth, non-absorbent surface of e-waste particles. In contrast, compressive strength dropped from 20.09 N/mm² to 10.43 N/mm², and flexural strength from5.25 N/mm² to 0.38 N/mm² as e-waste content increased. The mix with 5% e-waste achieved 18.12N/mm², close to the control, showing that small replacements maintain acceptable performance. Overall, e-waste improved workability but reduced strength, with 5% replacement identified as the optimum level for structural use. Using e-waste as a partial replacement for coarse aggregate is feasible up to 5%, giving the best compressive and flexural strength. Higher replacements (above 10%) reduce strength significantly. Further studies are recommended under real site conditions, for longer
curing periods, and in combination with other waste materials to improve performance.

The analysis of hydraulic flow in looped pipe networks is a fundamental yet computationally intensive task in civil engineering, traditionally addressed using the Hardy Cross method. Manual application of this method, however, becomes increasingly time-consuming and error-prone as network complexity grows. This study aimed to develop and validate an efficient computational tool for automating the Hardy Cross method using the Python programming language. The primary objectives were to implement the iterative algorithm, model hydraulic networks via structured Excel input, and rigorously validate the program's accuracy against benchmark problems. The methodology involved designing a modular Python program that utilized the pandas and NumPy libraries for data handling and numerical computations. The implementation supported both the Darcy-Weisbach equation, with friction factors calculated via the Swamee-Jain formula, and the Hazen-Williams equation for head loss determination. Network data including pipe length, diameter, roughness, and initial flow rates were organized in an Excel workbook, with each worksheet representing a distinct loop. The core algorithm iteratively computed flow corrections (ΔQ) for each loop until convergence was achieved, dynamically handling missing parameters and common pipes shared between loops using a sparse matrix approach.