Civil Engineering
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Civil Engineering
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Item Statistical Model for Predicting Slump and Strength of Concrete Containing Date Seeds(Covenant Journal of Engineering Technology (CJET), 2021) Yusuf, A; Jamal, J. O.; Abubakar, Mahmud; Aminulai, H. O.Incorporating agro-based waste in concrete can reduce environmental pollution and lead to preserving the ecosystem. In order to reduce trial and error in achieving desired slump and compressive strength of concrete containing Date Seed (DS), this paper examines the slump and compressive strength of concrete using date seeds as a partial replacement for crushed granite. Preliminary tests were conducted on the aggregates to ascertain their suitability for concrete production. Concrete with DS-crushed granite ratios of 0:100, 5:95, 10:90, 15:85, and 20:80 were prepared using a mix ratio of 1:2:4 and a water-cement ratio of 0.5. Slump loss was used to estimate the workability of the fresh concrete. The freshly prepared concrete was cast in 150 x 150 x 150 mm and the compressive strength was determined after curing by full immersion in water for 7, 14, 21 and 28 days. Results showed that the slump of concrete increased with an increase in the content of date seed. The compressive strength was inversely proportional to the date seed content with a DS crushed granite ratio of 20:80 recording the lowest compressive strength (20N/mm2). Linear regression models for slump and compressive strength were developed and found to be sufficient in explaining the experimental data based on a Mean Square Error (MSE) of 0.37 and 0.029 and R2 of 88% and 99% obtained for slump and compressive strength respectively. The study has concluded that DS can be used as a partial replacement for crushed granite in concrete and a linear model is sufficient in predicting the slump and strength of concrete containing date seeds.Item Numerical Investigation of Reinforced Concrete Beam Containing Iron Ore Tailings as Partial Replacement of Sand(Conference: 4 th International Conference on Innovations and Challenges in Engineering and Technology for Sustainable DevelopmentAt: Arba Minch University, Ethiopia, 2023) Abubakar, Mahmud; Haruna, M. I.; Abdulrahman, H. S.; Abbas, B. A.The production of industrial and agricultural residual by-products can generate significant environmental impact. In response, researchers have begun incorporating supplementary materials made from agro-industrial wastes to create more sustainable concrete. However, testing the performance of these waste-based concrete mixtures can be time-consuming and expensive. To address this issue, this study utilized three dimensional non-linear Finite Element simulation using the ABAQUS/CAE software to predict the behavior of a reinforced concrete beam that incorporated 20% IOT as partial sand replacement. The simulation successfully predicted the damage behavior of the 20% IOT concrete, indicating the potential of this modeling approach to accurately predict the performance of waste-based concrete mixtures in various designs.Item Development of a Simplified Methodology for British DoE Concrete Mix Design Procedure using python(Nile Journal of Engineering & Applied Sciences, 2025) Aguwa, Chinedu; Abubakar, MahmudMost of the methods of concrete mix design developed over the years were geared towards manual approach. Apart from being characterized by rigorous complication in computation, manual concrete mix design is prone to errors and mistakes inherent in the calculation during interpolations and reading of charts. Thus, this research introduces an innovative integration of Python algorithms into mobile applications for concrete mix design. The tables used in this algorithm are the same as those used in the British Method, however, Charts or Figures in the British method were converted into linear and polynomial equations. Python program was written to ease the use of the algorithm and it was also configured into the backend of a mobile application for user-friendliness. The results obtained from the algorithm were compared with those obtained based on the British method manual calculations and available datasets. The percentage errors between the algorithm results and manual calculations were found to range from 0.65% to 3% across all examples. The developed algorithm is a reliable tool for automating DoE concrete mix design. It is recommended for engineers to enhance accuracy and efficiency in mix design computations.Item ConcealedBeaminReinforcedConcreteStructures:APerformance-BasedAnalysis(NigerianJournalofScienceandEngineeringInfrastructure(NJSEI), 2024) Abubakar, Mahmud; Abdullahi, Hashim; Yabagi, Maikudi SaniThe use of hidden beams in reinforced concrete construction is seen as an effective method of reducing excessive deflection in large spans. However, despite its presumed advantages and growing usage, no mention of it in standard civil engineering literature, codes and standards. In this paper, performance-based analysis is carried out on three different cases of slab arrangement involving hidden beams using SAP2000. The process is performed under dead and live load combination and based on the design guidelines in BS8110. The result of the performance-based analysis shows a 4%, 2% and 11% decrease in deflection, stress distribution and area of bending steel reinforcement required for the case with hidden beam in comparison with the case without the hidden beam.This indicates that the presence of a hidden beam in a slab is significant. Thus, it is recommended for reducing excessive deflection in large spans, hidden beams can be introduced.Item Production of Pavement Blocks Using Low Density Polyethylene Product Waste(SETIC 2022 International Conference: “Sustainable Development and Resilience of the Built Environment in the Era of Pandemic” School of Environmental Technology, Federal University of Technology, Minna 6th – 8th February, 2023., 2023) Aboje, A. A.; Abbas, B. A.; Kolo, D. N.; Abubakar, Mahmud; Abdulsalam, A.Waste sachet water packs cause considerable land pollution in Nigeria. In this research, pavement block was produced using low density polyethylene products waste (sachet water packs) as an alternative binder. The production was achieved by first converting the sachet water packs into pellets and blending it with sandstone in a mass ratio of 8:2 (A), 7:3 (B) and 6:4 (C) sandstone to pellets respectively. The compressive strength, %water absorption and curing time tests were carried out on the pavement block to determine it suitability and safety for low-traffic use. The compressive strength for polymer concrete samples A, B and C were 13.65N/mm2, 16.99N/mm2 and 20.34N/mm2 respectively. After carrying out the %water absorption test on the polymer concrete A, B and C the following result was obtained: 8.33%, 5.47% and 4.03% respectively. It should be noted that the polymer concrete samples and the control samples which (are cement concrete based) are for light-traffic use (pedestrian, plazas, shopping complexes ramps, car parks, office drive ways, rural roads with low traffic, and residential road).Item POTENTIAL OF CALCIUM CARBIDE RESIDUE MODIFIED SANDCRETE BLOCKS IN ENHANCING THERMAL AND ENERGY EFFICIENCY FOR SUSTAINABLE BUILDING DESIGN(2nd Faculty of Engineering and Technology Conference (FETiCON 2024), Jun. 2 - 6, 2024, University of Ilorin, Nigeria, 2024) Ibrahim, M; Abubakar, Mahmud; Abdullahi, Aliyu; Abbas, B. A.Sustainability has increasingly become a prominent topic in the field of construction, and as such, it is necessary to explore means of reducing the overdependence on the use of cement in construction works. This study investigated the effects of calcium carbide residue (CCR) as a partial substitute for cement in sandcrete blocks. Due to the high pH value of calcium carbide residue, its disposal in landfills increases the alkalinity of the environment. From raw material extraction through final product disposal, the construction industry is integrally involved in every stage of the lifecycle of greenhouse gas emissions. In this study, cement was partially substituted using CCR at 0% and 12% by weight replacement. The sandcrete blocks were of 450 mm × 225 mm × 225 mm dimensions and made from a Cement-CRR mix ratio of 1:6 and water-cement ratio of 0.6. Preliminary tests such as consistency, setting times, soundness, and specific gravity tests were carried out on cement and cement + 12% CCR. The thermal properties, which include thermal conductivity (k), heat transfer coefficient (U), specific heat capacity (Cp) and diffusivity (α) of the sandcrete blocks were determined. The thermal tests were carried out after the 28th day of curing. The result showed that CCR increased the water demand by the sandcrete blocks, hence reducing its workability. The sandcrete block samples made with 12% CCR replacement showed improved compressive strength. The k for 0% and 12% replacement was 0.5497 W/mK and 0.3978 W/mK, respectively, while the U was 54.974 W/m2K and 39.784 W/m2K, respectively for the 0% and 12% replacement. On the other hand, the Cp for 0% and 12% was 0.0003364 J/kg°C and 0.0001598 J/kg°C, respectively, while the diffusivity was 636.54m2/s and 1113.94m2/s for 0% and 12% replacement, respectively. As such, we can infer that 12% CCR replacement of cement gives more energy-efficient and sustainable sandcrete blocks.Item Reliability Studies on Reinforced Concrete Column Subjected to Axial Load with Natural Stone as Coarse Aggregate(NAUJournalofCivil Engineering (NAUJCVE), 2024) Kolo, D. N.; Aguwa, J. I.; Abubakar, MahmudThis paper presents the reliability assessment of a reinforced concrete column subjected to Axial loading. Locally available natural aggregate (NA) was used in concrete production, the results of preliminary tests revealed the aggregate was adequate for concrete production. A typical column cross section of 230 × 240 × 3000mm was adopted and probabilistically assessed. First Order Reliability Method (FORM) was employed to estimate the implied probabilities of failures. The results of the sensitivity analysis showed that the reinforced concrete column is structurally safe at length, breadth and depth of 3200, 240 and 230 mm with Probability of Failures of 1.14 ×10-3, 8.45 × 10-4and 8.45 × 10-4 respectively.Item PROBABILITY-BASED CALIBRATION OF LOAD DURATION MODIFICATION FACTORS FOR THE NIGERIAN GROWN TIMBER(NIGERIA JOURNAL OF ENGINEERING AND APPLIED SCIENCES (NJEAS), 2023) Aguwa. J. I.; Sadiku, S.; Afolayan, J. O.; Abdullahi, A.; Abubakar, Mahmud; Kolo, D. N.All along, load duration modification factors used in Nigeria for design of timber structures were based on BS 5268 of 2002 and this is not a good engineering practice since the strength of timber depends so much on the soil as well as on the environment. There is the need to localize the modification factors based on our environment since Nigerian grown timber is generally used for all timber structures designed and built in Nigeria. Probability-based calibration of load duration modification factors for the Nigerian grown timber was successfully carried out. The results showed significant difference between the calibrated factors and those from BS 5268 of 2002. The calibrated modification factors are; 1.25 for long-term, 1.35 for medium-term, 1.70 for short term, and 2.0 for very short-term duration. This paper recommends the use of these calibrated load duration factors based on Nigerian grown environment.Item Optimization Of The Adsorption Process In Landfill Barrier Using Response Surface Methodology (Rsm)(IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE), 2024-04-17) Asogwa E.O; Adie D. B; Ibrahim F.B; Amadi. A.A; Saidu M; Adesiji A.R; Mangey J.AResponse Surface Methodology was used to examine the percentage of heavy metal removal from a sanitary landfill site utilising a lateritic soil-geopolymer composite. By Using the model, the lateritic soil geopolymer composite's adsorption potential was enhanced. The applicability of the employed model to predict the adsorption state is supported and confirmed by the good agreement between the observed and anticipated values of the removal efficiency. The applied models showed that all three of the components examined had an impact on the removal of heavy metals from sanitary landfill liners, but that the effects of dosage and contact time were more pronounced and had a substantial impact on the removal % of heavy metals. With dosage and contact time proving to be the most relevant of the three independent variables, the ANOVA findings show that the model parameters are significant. After refining the replies, the following settings proved ideal: dosage of 10g, contact time of 48 hours, and temperature of 50 °C. These yielded percentage removals of lead, zinc, and copper of 97.88%, 94.36%, and 99.48%, sequentially. Keywords: Heavy Metals, Geopolymer, Landfill, Barrier, Optimization, Lateritic-soil, Response Surface Methodology (RSM)Item Structural Assessment of a Lattice Tower in Federal Capital Territory, Abuja(Nigeria Journal of Engineering and Applied Sciences (NJEAS), 2022-01-02) Auta, S. M.; Okunyomi, O. O.; Kolo, D. N.Since the licensing of GSM operators in Nigeria from 2001, there was an astronomical increase in construction and maintenance towers. In a bid to reduce maintenance cost, tower sharing was adopted by some telecommunication providers. The Nigerian Communications Commission guidelines for installation of masts and towers stipulates that all lattice towers should be checked for their structural health status every five years. This requirement has promoted this research work. The objective of the study includes selection of a lattice with weakest parameters, determine the tower’s structural stability and its utilization percentage. A 45m tower with 3-legs erected over 8 years and shared by three telecommunication operators in the Federal Capital Territory (FCT) was selected. Audit was conducted on the tower and its foundation. There were no warped member and no visible crack on the tower foundation. The average compressive strength of the stub columns determined using the digital Schmidt hammer were 25.1, 25.9 and 25.9 N/mm2 for legs A, B and C. From the structural analysis using the EPA model, the tower utilization percentage was found to be at 59.4% after optimization. The STAAD pro. V8i analysis showed that the utilization ratio of the tower members is ≤ 1. Furthermore, design properties for the tower members are less than the properties of the actual tower members used and there was no failed member identified after the structural analysis. In conclusion, the lattice tower can be said to be stable and fit for continuous use.