Browsing by Author "Abubakar, Mahmud"

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Analysis of Statically Determinate Trusses using Exact Method (Joint Resolution Method) and Matrix Stiffness Method
(USEP: Journal of Research Information in Civil Engineering, 2017) Abdullahi, A.; Yusuf, I. T.; Abubakar, Mahmud; Aminulai, H. O.; Yusuf, A.; Alhaji, B.
Matrix Stiffness Method (MSM) as a tool for static analysis of structures is premised on the principle of Finite Element Method (FEM), which in itself is a numerical/approximate method capable of giving only approximate results. However, Joint Resolution Method (JRM) is one of the most popular classical/exact methods of static analysis capable of giving exact results. This paper presents an analysis of a statically determinate 2-D truss using Exact/Joint Resolution Method (JRM) and Matric Stiffness Method (MSM) to ascertain the validity of the latter against the former. In the JRM, the support reactions and internal member forces were obtained from considerations of the equilibrium conditions of the entire truss and isolated joints respectively. On the other hand, a computer program was written in MATLAB 7.8.0 (R2009a) based on the principles of MSM for ease of computation and increased accuracy to solve for member forces and reactions of the same truss. The element properties were obtained and employed to calculate the element stiffness matrices, these were then assembled into the global stiffness matrix, from which the unknown displacements, member forces and support reactions were calculated. The results obtained from using both JRM and MSM were found to be exactly the same or very close, with percentage errors ranging between 0% and 3%. Hence MSM results as compared to JRM have 97% accuracy and above, and can therefore be relied upon.
Assessment of the Compressive Strength of Concrete Produced with Fine Aggregate from Different Locations in Minna
(3rd International Engineering Conference (IEC 2019) Federal University of Technology, Minna, Nigeria, 2019) Aminulai, H. O.; Abdullahi, A.; Abubakar, Mahmud; Abdulrahman, H. S.; Alhaji, B.; Joseph, O. F; Aliyu, S. Y
The construction industry in Nigeria has been witnessing serious collapse of buildings resulting from the qualities of materials used in their construction. This continuous collapse necessitates the need to investigate some of the materials used in the production of the building components in order to ascertain their appropriateness. This research thus investigates the compressive strength of concrete produced using fine aggregate from different locations in Minna. Fine aggregates were obtained from Chanchaga, Maikunkele, Bosso, Lapai Gwari and Garatu areas of Minna and subjected to series of tests namely: sieve analysis, Specific gravity, bulk density, moisture content, and water absorption. Concrete samples were produced using the mix ratio 1:2:4 and the water/cement ratio of 0.6. These samples were subjected to both the slump test and compressive strength test. For each of the fine aggregates, nine cubes of concrete (150mm x 150mm x 150mm) were cast, cured and tested at 7, 14 and 28 days. The results obtained for the mean compressive strength of the concrete produced shows that they all have mean strength greater than 20N/mm2 with fine aggregate from Chanchage having the highest mean of 25.17N/mm2 at 28days of curing. Thus all the fine aggregates could be used in the production of structural lightweight concrete but for structures that require higher strength, the fine aggregate from Chanchaga is recommended
COMPARATIVE ANALYSIS OF TRAFFIC PERFORMANCE OF SMALL AND LARGE CENTRAL ISLAND ROTARIES IN MINNA, NIGERIA
(SAVAP International, 2013) Abubakar, Mahmud; Ndoke, P. N.
Of recent, the government of Niger state has embarked on the construction of roundabouts with small central island rotaries; this paper compares the performance of large central island rotaries with small central island rotaries. The performance of large central island rotaries compares well to the performance of small central island rotaries. Capacities of rotaries with small islands were found to be higher than capacities of large central island rotaries while the delay for large central island rotaries was found to be higher than that of small central island rotaries. However, both large and small central island rotaries were found to be operating at the same level of service. This study provides recommendations to traffic engineers and/or planners on the conditions under which both central island rotaries perform better and, thus, should be considered.
Comparative Assessment of Macroscopic Traffic Flow Properties Estimation Methods: A Case for Moving Car Observer Method
(ENGINEERING SCIENCE AND TECHNOLOGY INTERNATIONAL RESEARCH JOURNAL, 2017) Hassan Shuiabu Abdulrahman; A. A. Almusawi; Abubakar, Mahmud
Different methods of estimating macroscopic traffic properties is expected to have varying results even when they are carried out on the same road and during the same time interval. A comparative assessment was carried out between traffic data collected at a point and that collected over a short section; Moving car observer method(MCO). Student’s t-test was used to evaluate both data and it was observed that there was no significant difference between them. The MCO method correlates well with conventional data collection method and it can be used as a substitute for it, assuming conventional data collection method is true
Comparative Assessment of Macroscopic Traffic Flow Properties Estimation Methods: A Case for Moving Car Observer Method
(ENGINEERING SCIENCE AND TECHNOLOGY INTERNATIONAL RESEARCH JOURNAL, 2017) Abdulrahman, H. S.; Almusawi, A. A.; Abubakar, Mahmud
Different methods of estimating macroscopic traffic properties is expected to have varying results even when they are carried out on the same road and during the same time interval. A comparative assessment was carried out between traffic data collected at a point and that collected over a short section; Moving car observer method(MCO). Student’s t-test was used to evaluate both data and it was observed that there was no significant difference between them. The MCO method correlates well with conventional data collection method and it can be used as a substitute for it, assuming conventional data collection method is true
Comparison of Drying Shrinkage Models of IOT Concrete
(2nd International Engineering Conference (IEC 2017) Federal University of Technology, Minna, Nigeria, 2017) Oritola, S. F.; Saleh, A. L.; Mohd Sam, A. R.; Abubakar, Mahmud; Alhaji, B.
Problems associated with drying shrinkage of concrete is still a major source of concern in the construction industry. Due to the hygral nature of concrete, particularly the instability of the volume as a result of drying shrinkage, concrete will crack at any stage during its service life. The depletion of the environment due to huge consumption of sand for construction is another major problem. Iron ore tailings (IOT), an industrial waste, generated during the production of iron ore is utilized in concrete to lessen the environmental problems. The iron ore tailings was sourced from a local iron ore producing mine and the material was used as partial replacement for sand to produce normal weight concrete. The drying shrinkage of this concrete was compared with that of the control normal weight concrete. The ultimate drying shrinkage of the concrete samples were further studied, using three prediction models. The inclusion of iron ore tailings as fine aggregate in concrete contributed to reduction of the drying shrinkage recorded at 28, 56 and 90 days as well as the ultimate drying shrinkage. The drying shrinkage of concrete and the predicted ultimate drying shrinkage recorded by the B3 and GL2000 models agreed more closely, as compared with the recorded values obtained using ACI209R model.
ConcealedBeaminReinforcedConcreteStructures:APerformance-BasedAnalysis
(NigerianJournalofScienceandEngineeringInfrastructure(NJSEI), 2024) Abubakar, Mahmud; Abdullahi, Hashim; Yabagi, Maikudi Sani
The 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.
Development of a Simplified Methodology for British DoE Concrete Mix Design Procedure using python
(Nile Journal of Engineering & Applied Sciences, 2025) Aguwa, Chinedu; Abubakar, Mahmud
Most 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.
DEVELOPMENT OF AN ANDROID BASED MOBILE APPLICATION FOR THE DESIGN AND DETAILING OF ISOLATED PAD FOUNDATIONS ACCORDING TO EUROCODE 2
(i-manager’s Journal on Mobile Applications & Technologies, 2019) Yusuf, Abdulazeez; Isiaka, I.; Abubakar, Mahmud; Aminulai, H. O.; Abdullahi, Aliyu; Alayande, T. A.
In a building construction project, it is the responsibility of the structural engineer to come up with a complete design of all structural elements. When this is done manually it is tasking, time consuming, and produces errors with inconsistent results. However, the design can be done using computer software, but this also comes with some downside; it is expensive and complex to use. Thus, this research developed an android based mobile application for the design of pad foundations to Eurocode 2 to put these challenges in check when designing pad footings. The mobile application designs isolated Axially loaded-only and Axially loaded with bending pad footing to Eurocode 2 accurately, with consistent results and in a timely manner. The application was tested using typical test parameters and results are compared to the manual computations. There was no significant difference in the steel sections provided for both methods. All checks that must be satisfactory in design were all checked and found to be satisfactory.
Development of an Android Based Mobile Application for Design and Detailing of Pad Foundations to BS8110
(Epistemics in Science, Engineering and Technology, 2017) Yusuf, A.; Aminulai, H. O.; Abdullahi, A.; Abubakar, Mahmud; Alhaji, B.
Many innovative computer software have been developed to perform the task of designing and detailing structural elements such as beams, columns, slabs and foundations. This design and detailing can be done using mobile devices but software developed to operate on such devices have not been fully developed. However, this research is aimed at developing an android based mobile application for the design of pad foundations to Bs8110. The mobile application developed designs isolated axially loaded-only; axially loaded with moment pad footings as well as combined pad footings. The mobile application developed was tested using three typical test parameters and results compared to the manual computations. There was no significant variation in the steel sections required and provided for the manual design and that generated by the mobile application. The steel required by manual design for the axially loaded pad footing was 835mm2/m and that generated by the application was 837.2mm2/m. That of the axially loaded with moment gave required steel section as 1019mm2/m using manual design. This android based mobile application would thus give the structural engineer the leverage to design pad footings anywhere and anytime.
Development of an Android Based Mobile Application for Design and Detailing of Pad Foundations to BS8110
(Epistemics in Science, Engineering and Technology, 2017) Yusuf, A.; Aminulai, H. O.; Abdullahi, A.; Abubakar, Mahmud; Alhaji, B.
Many innovative computer software have been developed to perform the task of designing and detailing structural elements such as beams, columns, slabs and foundations. This design and detailing can be done using mobile devices but software developed to operate on such devices have not been fully developed. However, this research is aimed at developing an android based mobile application for the design of pad foundations to Bs8110. The mobile application developed designs isolated axially loaded-only; axially loaded with moment pad footings as well as combined pad footings. The mobile application developed was tested using three typical test parameters and results compared to the manual computations. There was no significant variation in the steel sections required and provided for the manual design and that generated by the mobile application. The steel required by manual design for the axially loaded pad footing was 835mm2/m and that generated by the application was 837.2mm2/m. That of the axially loaded with moment gave required steel section as 1019mm2/m using manual design. This android based mobile application would thus give the structural engineer the leverage to design pad footings anywhere and anytime.
Durability of Sun Dried Clay Bricks Admixed with Cow Cone ash for Sustainable Development
(USEP: Journal of Research Information in Civil Engineering, 2022) Abubakar, Mahmud; Abdullahi, Hashim; Yabagi, Maikudi Sani; Adamu, Hawawu Nana
Housing has remained a major challenge in Nigeria because of the increasing population and cost of building materials. To tackle the problem of housing deficit in the country, the government of Nigeria for some time now has been clamoring for the use of local materials in the construction industry to limit costs of construction. Thus, this paper looks at the potential of using cow bone ash (CBA) to improve the durability of sun dried clay brick for sustainable development. Consistency properties, shrinkage, compressive strength and crack behavior of clay-cow-bone ash bricks were investigated in accordance with relevant codes and standards. It was however observed that, consistency properties and shrinkage decreased with increased percentage cow-bone ash addition while compressive strength and crack improved up to 10% CBA addition indicating that buildings made of clay-CBA composite could be more stable and durable than the ones made from clay alone. It is therefore recommended that Cow-bone ash can be used to improve the durability of clay brick at optimum addition level of 10%. Clay brick admixed with cow bone ash strongly contributes to the attainment of 12 out of the 17 sustainable development goals.
EFFECT OF PARTIAL REPLACEMENT OF FINE AGGREGATE WITH SAWDUST IN LIGHT WEIGHT CONCRETE PRODUCTION USING BIDA NATURAL STONE AS COARSE AGGREGATE
(3rd International Engineering Conference, Federal University of Technology, Minna, Nigeria, 2019) Alhaji, Bala; Abubakar, Mahmud; Yusuf, A.; Oritola, S. F.; Mohammed, S.; Kolo, D. N.
This study investigated the effect of sawdust as partial replacement for Fine Aggregate in light weight concrete production. Sawdust was used to replace Fine Aggregate from 0% to 40% in steps of 5%. 150 x 150 x 150mm concrete cubes were cast for each replacement level, the concrete was cured and the compressive strengths were determined at 7, 21 and 28days curing period respectively. Increase in percentage of sawdust in concrete led to a constant reduction in the compressive strength values with a corresponding reduction in weight. From the result obtained, 5% replacement of Fine Aggregate with sawdust gave a maximum compressive strength 13.11 N/mm2. It was however concluded that the optimum replacement level of 5% can be used as plain concrete for blinding works.
Effectiveness of Locust Bean Epicarp Extract on Re-vibrated Concrete Using Pebbles from Bida Environs as Coarse Aggregate
(Sustainable Education and Development—Clean Energy Proceedings of the Applied Research Conference in Africa (ARCA), 2023, 2023) Abbas, Bala Alhaji; Mohammed, Tahir Abdul,; Yusuf, Abdulazeez; Kolo, Daniel Ndakuta; Abubakar, Mahmud; Abdullahi, Aliyu
In this research, the effect of re-vibrated concrete using locust bean epicarp extract and Bida natural stone (Pebbles) as coarse aggregate was presented. Design/Methodology/Approach: The concrete mix of 1:2:4 and water cement ratio of 0.5 was adopted respectively. One hundred and sixty-eight (168) concrete cubes were produced in six (6) batches, 28 cubes were produced for control (mix A = 0% LBEE + 100% OPC) and 28 for (0, 5, 10, 15 and 20%) cement reduction respectively. Findings: The results of preliminary test of the aggregates indicate that they are suitable for concrete production and the chemical analysis of LBEE showed that it is a very good pozzolana. Concrete cubes were cast with re vibration time lag intervals of 10 min for the period of 60 min re-vibration process and cured for 7 and 28 days. The result shows that introduction of LBEE improve the compressive strength of concrete. The result obtained also shows that there is increase in compressive strength with the increase in re-vibration time lag of LBEE concrete, hence the maximum compressive strength was obtained at 60 min for all batches. The maximum compressive strength obtained at 28 days curing was 35.70 N/mm2 for B (0% cement reduction) at 60% re-vibration which is higher than 34.0 N/mm2 for control mix A. The optimum cement reduction of concrete made incor porating LBEE without re-vibration and the one with re-vibration is 5% and 20% respectively. Practical Implications: This types of concrete can be used for struc tural application such as in the construction of reinforced concrete slabs, beams, columns and foundations. Social Implications: In order to provide adequate housing for over increasing population of people in Bida and Environs the use of Locust Bean Epicarp Extract on Re-vibrated Concrete Using Pebbles from Bida as coarse aggre gate should be encouraged by individuals and government at all levels. This will also lead to reduction in construction cost of houses in Nigeria and create employment to the rural dwellers where locust bean trees are grown. Originality and Value:This study contributed to the pool of knowledge on how Locust Bean Epicarp Extract and concrete Re-vibration has improved the strength of concrete. Thus 20% and 5% is recommended as the optimum cement reduction of concrete made incorporating LBEE with re-vibration and the one without re-vibration respectively.
EFFECTS OF IRON ORE TAILINGS (IOT) ON THE MECHANICAL PROPERTIES OF CONCRETE
(Conference Proceedings, 1st Faculty of Engineering and Technology Conference (FETiCON 2023), Jun. 5 - 7, 2023, University of Ilorin, Nigeria, 2023) Balarabe, F.; Abubakar, Mahmud
A lot of research has shown that iron ore tailings (IOT) is not only a source of pollutant but also has good pozzolanic properties. However, the behaviour of IOT concrete in service is yet to be fully reported. This research investigates the effect of IOT on the mechanical properties of concrete whose fine aggregates is partially replaced with IOT. Fine aggregates content in concrete of mix ratio 1:2:4 of 10 to 40% was replaced with IOT. Young’s modulus and Poisson ratio of the resulting concrete beams were determined by compression test. The results showed that 20% replacement of fine aggregates by IOT in the concrete mix gave the best mechanical properties of the resulting concrete. The Young’s modulus of the concrete was seen to increase by 26.53% when with 20% IOT content when compared to that without IOT. The Poisson ratio at 20% IOT content was seen to also decrease by 61.54% when compared to that without IOT. As such, 20% IOT for fine aggregate content replacement in concrete mix 1:2:4 is recommended for structural uses.
Hygrothermal Effects of Partial Replacement of Coarse Aggregates with Palm Kernel Shell in Concrete Production
(Nigerian Journal of Engineering and Applied Sciences (NJEAS), 2017) Abdullahi, A; Abubakar, Mahmud; Aminulai, H. O.; Yusuf, A.; Alhaji, B.
Hygrothermal effects of partial replacement of coarse aggregates with Palm Kernel Shell (PKS) in concrete production were assessed. Preliminary tests were conducted on PKS to determine its suitability for use as aggregate in concrete production. Workability and Density of the fresh concrete were also determined. Cylinders of 100mm diameter by 50mm height were used to cast the concrete; these were cured for 28 days and tested for water absorption and sorptivity at different replacement levels of coarse aggregates with PKS. The sorptivity of concrete was found to increase with increase in PKS content, however, between 5-25% PKS content, lower sorptivity values than control were recorded. Water absorption of concrete also increased with increase in PKS content, PKS contents from 5-20% gave water absorptions below the control and at 25% replacement, a slightly higher value as compared to the control was recorded. From the results obtained, concrete with 5% PKS content was found to possess the best water absorption as well as sorptivity values. Such concrete adequately fits for use in areas where concrete water absorption and sorptivity are required to be kept at a very minimal level; such as in the construction of drainages and dams.
Investigation of headway distribution of traffic dominated by motorcycles
(8th Advanced Engineering Days (AED) – 8 December 2023 – Mersin, Türkiye, 2023) Abdulrahman, H. S.; Kolo, S. S.; Abubakar, Mahmud; Shehu, M.
The use of lower class vehicles such as two or three wheelers have become the preferred urban transport in some developing countries. However, most of the traffic theories adopted are from developed countries where cars are prevalent. The headway probability distribution models can be used to describe vehicle-to-vehicle interactions. Most of these distributions are parametric and makes an underlining assumption about the data. A case study was conducted to investigate the performance of the different probability distributions that best describes the vehicle to vehicle interaction of motorcycle dominated road in Bida, Niger state Nigeria. The different parametric distributions and non-parametric distribution (Kernel) of the data were tested for the goodness-of-fit. The test results indicate that the kernel distribution fits best with improved P-values which in turn gives a better description for the headways than other distribution models considered. This study can serve as a foundation for developing generalized headway models in developing countries
Modelling the Slump, Compressive Strength and Density of Concrete Containing Coconut Shell as Partial Replacement for Crushed Granite
(USEP: Journal of Research Information in Civil Engineering, 2017) Abdullahi, M.; Aminulai, H. O.; Alhaji, B.; Abubakar, Mahmud
In this research, crushed coconut shell was used to partially replace crushed granite as coarse aggregate in the production of concrete. Tests were conducted on the physical properties of crushed coconut shell and crushed granite. Thirty one random mixes were generated using Mini Tab 14 statistical software package. A total of 108 cubes were cast and cured for 28 days and then crushed to determine their compressive strength. The results were used to develop empirical models for the slump, compressive strength and density of the concrete. The concrete developed in this work has slump ranging from 0 – 135 mm, compressive strength ranging from 8.94 N/mm2 – 27.11 N/mm2 and density ranging from 1757.04 kg/m3 to 2198.52 kg/m3 respectively. This implies that concrete made using coconut shell as partial replacement for crushed granite can be used for structural application such as in the construction of reinforced concrete slabs, beams, columns and foundations. Polynomial model was developed with the capability of explaining the under-laying relationship of 93.8%, 83.6% and 72.3% for slump, compressive strength and density respectively.
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.
Optimization of Cement-Based Mortar Containing Oily Sludge Ash byResponse Surface Methodology
(Materials, MDPI, 2021) Kankia, Mubarak Usman; Baloo, Lavania; Danlami, Nasiru; Samahani, Wan Nurliyana; Mohammed, Bashar S.; Haruna, Sani; Jagaba, Ahmad Hussaini; Abubakar, Mahmud; Effa, Affiana Ishak; Khalid, Sayed; Zawawi, Noor Amila Bt Wan
In the industries of petroleum extraction, a large volume of oily sludge is being generated. This waste is usually considered difficult to dispose of, causing environmental and economic issues. This study presented the novel experimental method of manufacturing mortar used in civil construction by cement and oily sludge ash (OSA). The defined method was described with a logical experimental study conducted to examine a feasible manufacturing method for casting cement-based mortars by partially replacing cement with OSA. Replacement concentrations for OSA ranged from 0 to 20 percent by cement weight, while the water-to-cement (w/c) ratio was varied from 0.4 to 0.8, and the amount of sand was kept constant. The strengths and absorption rate of the mortar were monitored for 28 days. The OSA contains a crystalline structure with packs of angular grains. Because of OSA in the cement-based mortar mixtures and water-to-cement ratios, the mechanical strength was improved significantly. However, the water absorption trend increased linearly. Using variance analysis, the influence of OSA and w/c ratio on the behavior of mortar was acquired. The developed models were significant for all p-value reactions of <5%. Numerical optimization results showed that the best mixture can be obtained by replacing 8.19 percent cement with OSA and 0.52 as a ratio of w/c.