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.
Comparison of Drying Shrinkage Models of IOT Concrete
(Conference: 2nd International Engineering Conference (IEC 2017) Federal University of Technology, Minna, Nigeria, 2017) Oritola, S. F.; Abd Latif, Saleh; Abdul Rahman, Mohd.Sam; 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.
Design of A Composite Traffic Control System at Kpakungu Roundabout Minna, Niger State
(Nigeria Journal of Engineering and Applied Sciences (NJEAS), 2016) Kolo, S.S.; Adeleke, O. O.; Ayeni, S. J.; Akinmade, T.; Abubakar, Mahmud; Yusuf, A.
A composite traffic control method is proposed to control traffic and ease congestion especially during peak periods at Kpakungu roundabout in Minna, Niger state. Reconnaissance survey of the roundabout was carried out to note predominant directions of traffic flow from each approach to the roundabout; manual counting of traffic for five working days was done between 7:00 am to 12 noon and 3:00 - 7:00 pm daily. The result of the survey shows that congestion occurs at the roundabout between 7:45 - 9:30 am and between 5:00-6:30 pm every day. Results also show that the peak hourly traffic flow rate occurs between 8:00 and 9:00 am, and 5:00 to 6:00 pm daily. The result of the traffic count was then forecasted for 2-years using data on annual vehicle registration in Minna for 2011 to 2015 obtained from the Niger State Board of Internal Revenue Service. The Webster method of signal timing was used to design traffic signals that will optimally allocate right of way time to conflicting traffic streams. A 5-phase signalization of 90- and 97-seconds cycle lengths were proposed for morning and evening peak periods, respectively.
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.
Effect Of Water Cement Ratio On The Compressive Strength Of Revibrated Concrete
(Environmental Technology and Science Journal, 2015) Auta, S. M.; Abubakar, Mahmud; Yusuf, A.
Effect of water cement-ratio on compressive strength of re-vibrated concrete is presented. The mix proportion of 1:2:4 aggregates were considered to cast 39 cubes each as laboratory specimen with 0.65, 0.70 and 0.75 water-cement ratios. Each of these categories were revibrated at time lag intervals of 10minutes for 120 minutes period of revibration process and cured for 7, 21 and 28 days. When tested for their respective compressive strength, the result obtained shows that there is a gradual increase in compressive strength of the concrete specimen with increase in time and in water-cement ratio. The maximum compressive strength at 120th minute for ages of 28 days are 25.42, 26.67 and 40.44N/mm2 for concrete with water-cement ratio of 0.65, 0.70 and 0.75 respectively. The maximum attained compressive strength for 28 days curing is 40.44N/mm2 (for 0.75w/c) appears to be higher than 25.42N/mm2 (for 0.65 w/c). Water-cement ratio has adversely enhanced the compressive strength of concrete when re-vibrated.
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.
Effects of Waste Glass Powder and Cassava Peel Ash on Compressive Strength of Concrete
(Proceedings of the Third International Civil Engineering Conference (ICEC, 2024), 2025) Ndaiji, A. U.; Abdullahi, M.; Abbas, B. A.; Abubakar, Mahmud
This study investigates the effects of incorporating glass waste powder (GWP) and cassava peel ash (CPA) as partial replacements for cement on the compressive strength of concrete. A total of 294 concrete cubes were prepared with varying proportions of GWP and CPA (0%, 5%, 10%, 15%, 20%, 25% and 30% replacement levels). Both materials were characterized by X-Ray Fluorescence (XRF) analytical method. The slump of fresh concrete with WGP and CPA of 0, 5, 10, 15, 20, 25 and 30% respectively by weight of cement was investigated in accordance with standard procedures. The results show that the compressive strength of concrete increased with the addition of GWP and CPA up to a certain replacement level. The 28 days compressive strength of concrete with 15% WGP/CPA content was 16.4 % more than normal, while that of concrete with 20% WGP/CPA content was 11.9 % less than normal. The optimal replacement levels for GWP and CPA were found to be 15% and 5%, respectively. The study concludes that the use of GWP and CPA as partial replacements for cement can improve it compressive strength, it sustainability and reduce the environmental impact of concrete production. The results of slump tests of different percentages of CPA/GWP as a partial replacement of cement in concrete production were observed for all proportion ranging between 12 – 41mm. However, 20% GWP/CPA replacement was considered as optimum for structural concrete.
Estimation of Pavement Temperature in Nigeria’s Climatological Zones
(Proceedings of the Third International Civil Engineering Conference (ICEC, 2024), 2025) Ibrahim, A. I.; Abdulrahman, H. S.; Abubakar, Mahmud