Civil Engineering

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Effect of Partial Replacement of Cement with Cow Dung Ash Using Bida Natural Coarse Aggregate
(School of Environmental Technology, Federal University of Technology, Minna, 0022-10-05) Abbas, B. A.; YUSUF, Abdulazeez; Kolo, D. N; Aboje, A. A.; Mahmud, M.B.; Ndaiji, A. U.
The research investigates the effect of partial replacement of cement with cow dung ash (CDA) in concrete production using Bida natural coarse aggregate. Water to cement ratio and mix ratio of 0.6 and 1:2:4 was adopted respectively. The aggregates used were characterized and the cow dung was calcined at a temperature between 400-500oC. Concrete was produced using CDA as cement replacement at 0%, 5%, 10%, 15%, 20%, 25%, 30%, 35% and 40%. Slump of the freshly produced concrete was determined and the compressive strength of the hardened concrete was determined at 7, 21 and 28 days of curing. The sum of SiO2, Al2O3 and Fe2O3 in CDA exceeds the 70% minimum specified by ASTMC 618-12. The slump of the fresh concrete ranges from 0 – 40 mm while the compressive strength at 28 days curing duration ranges from 12.59N/mm2 19.29N/mm2 and density was 2323.95kg/m3– 2554.59kg/m3 respectively. The test results revealed that the compressive strength decrease with increase in CDA content and increase with curing age. The strength results indicate that there was no much significant difference between the control specimen with 0% CDA and that containing 5% CDA. This implies that concrete made using CDA as partial replacement for cement can be used for structural applications such as in the construction of reinforced concrete slabs, beams, columns and foundations. The study concluded that CDA has pozzolanic properties and can be used to replace up to 10% cement in concrete produced using Bida natural coarse aggregate.
Partial Replacement of Sand with Sawdust in Concrete Production
(3rd Biennial Engineering Conference, Federal University of Technology, Minna, May, 2013, 2013) Abdullahi, A.; Abubakar, Mahmud; Afolayan, A.
The rising costs of building construction in developing countries have been a source of concern to government and private developers. This study investigated the use of sawdust as partial replacement for fine aggregates in concrete production. Sawdust was used to replace fine aggregates from 0% to 50% in steps of 10%. Concrete cubes measuring 150 x 150 x 150mm were cast and their compressive strengths evaluated at 7, 14, 21 and 28 days. Increase in percentage of sawdust in concrete cubes led to a corresponding reduction in compressive strength values. From the results, the optimum sawdust content was obtained at 10% and its corresponding compressive strength at 28 days is 7.41 N/mm2 which falls within the characteristic strength of plain concrete (7 – 10 N/mm2). This concrete cannot be used for structural applications.
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.
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.
Design of A Composite Traffic Control System at Kpakungu Roundabout Minna, Niger State.
(Nigeria Journal of Engineering and Applied Sciences (NJEAS), 2016-08-10) Kolo S.S; Adeleke O. O; Ayeni S. J; Akinmade T; Abubakar M.; YUSUF, Abdulazeez
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.
Dimensional Compliance and Compressive Strength of Sandcrete Hollow Blocks Produced in Minna Metropolis
(International Engineering Conference (IEC 2017) Federal University of Technology, Minna, Nigeria, 2017) Yusuf, Abdulazeez; Aminulai, H.O.; Abdullahi, A; Alhaji, B; Alalade, A.I.
The study was carried out to investigate the level of dimensional compliance of commercially produced sandcrete blocks in Minna metropolis and also determine the compressive strength of collected block samples. One hundred and sixty (160), nine (9) inch hollow sandcrete block samples were collected from ten sandcrete block producing companies. Fine aggregate samples were collected from the hollow sandcrete block companies along with the hollow sandcrete blocks. Sieve analysis was carried out on the soil samples. Density, water absorption and dimension of the collected Sandcrete block samples were determined. Compressive strength at 7 and 14 days curing age was also determined. Results indicate that the fine aggregates used were not suitable for block making as the coefficient of uniformity of soil samples range from 0.71 – 1.89 while the coefficient of curvature lie within 2.57 to 4.80 which do not conform to standard. None of the Sandcrete block production company met the required standard dimension as specified by Nigeria Industrial standard (NIS). Test results also revealed that the water abortion capacity of all collected block samples were below 12% maximum recommended by NIS except for block industry M which recorded 12.08%. The density was between 1.59 g/cm3 – 5.05 g/cm3, greater than 1.5g/cm3 specified by NIS. The average compressive strength was between 0.21N/mm2 - 1.11N/mm2 at 14 days curing age which was less than 3.45 N/mm2 specified by NIS. It was recommended that block producing industries should be enforced by the standard organization of Nigeria to follow the recommended standard dimensions by carrying out routine check.
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.
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.
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.
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.
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.
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
(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.
Assessment of Safety Provisions on Building Construction Sites in Abuja, Nigeria: Professionals and Workers Perspectives
(Proceedings of the 2nd International Engineering Conference, Federal University of Technology Minna, Nigeria., 2017-01-02) Kolo, D. N.; Yitmen, I.; Tsado, T. Y.; Abdullahi, M.; Yakubu, D. M.
Despite the growth of the building construction sector in Nigeria, the provision of the basic safety materials and facilities to workers remains a challenge. The construction industry is believed to be a pillar of domestic economy in most nations; it is believed to contribute about 2.08% to the GDP of Nigeria. Yet, the rate of non-fatal, fatal injuries and illnesses exceeds that of many other industries, the construction industry has the most fatality rate when compared to other industry sectors. This paper examines the level of provision of the basic safety materials and facilities to workers by contractors in the Nigerian construction industry, the study employed the work study and field survey research method. Structured questionnaire were administered to the Architects, Engineers, Project managers and Contractors as well as the workers engaged in construction. The research exposed the neglect in the provision of safety materials and facilities on the part of the contractors. Scaffolds and shovels where the materials readily provided by the contractors from the list of safety materials provided as recommended by the regulatory authorities. The Institute of safety professionals of Nigeria, Council of registered builders of Nigeria and other statutory government agencies should be more diligent to effectively monitor the activities of building construction contractors in Abuja, Nigeria.
Analysis of Statically Determinate Trusses using Exact Method (Joint Resolution Method) and Matrix Stiffness Method
(USEP: Journal of Research Information in Civil Engineering, 2017-10-10) A. Abdullah; I. T. Yusuf; M. Abubakar; H. O. Aminulai; YUSUF, Abdulazeez; B. Alhaji
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.
Computer-aided analysis of reinforced concrete waffle bridge deck using the method of grillages
(International Civil Engineering Conference (2018) (ICEC2018)., 2018) Adamu, H. N.; Sadiku, S.; Bala Alhaji
This paper aims to analyse a reinforced concrete waffle bridge deck using method of grillages where the topping and ribs are analysed as a monolithic unit in contrast to the conventional methods where the slab and beams are analyzed differently. In addition, the grillage approach accounts for the torsion that is usually lost in the conventional approach. The slab loading is in line with the HA loading of the BS 5400 part 2 for lightly loaded (accommodation) bridges. One of the strength of this approach is that it is amenable to computer application which has been demonstrated by using a code written in Matrix Laboratory (MATLAB) software and therefore easy for field use by practitioners. For the purpose of rendering this approach amenable to computer application, a program was used to determine the displacements, bending moments and torsional moments in the bridge deck. It is observed that the values of bending moments obtained from grillage analysis are lower than the moments from conventional beam-slab analysis carried out manually. Bending moments and other responses generated by conventional beam-slab approaches are usually exaggerated thereby reducing the anticipated benefits of waffle slab.
Barriers to the Adoption of Building Information Modelling in Nigerian Construction Industry
(Proceedings of the 1st International Civil Engineering Conference, Department of Civil Engineering, Federal University of Technology Minna, Nigeria, 2018-01-02) Kolo, D. N.; Tsado, T. Y.; Bala, A.; Adinoyi, S. A.; Kolo, D. N.
Building Information Modeling (BIM) involves the development and use of computer generated n-D models to simulate, plan, design, construct, adapt, operate, maintain, renovate, and ultimately beneficially deconstruct a building at the end of its life cycle. BIM represents a new paradigm in construction, it encourages the integration of roles of construction stakeholders enabling them to visualize the project to be built and further identifying potential issues that may occur during the operational phase of buildings. This study assessed the barriers to the adoption of BIM in the Nigerian construction industry and further highlighted ways to improve its adoption. A total of 50 questionnaires were administered to construction professionals in Abuja, Nigeria. Forty (40) retrieved questionnaires were analysed using Statistical Package for social Sciences (SPSS 21) and used for this study, it was revealed that there was generally a low awareness on the use of BIM among construction professionals. The major barrier to using BIM was lack of skilled personnel while the major means of ensuring its adoption was Provision of basic BIM infrastructure. These problems can be effectively tackled by increased support from government and construction industry stakeholders for its use; stressing the benefits derivable, training and retraining of key construction professionals taking into consideration peculiarities to the Nigerian construction industry.
ASSESSMENT OF THE PROPERTIES OF HIGH STRENGTH CONCRETE MADE USING QUARRY DUST AS FINE AGGREGATE
(2018-09-22) Mohammed T.A.; YUSUF, Abdulazeez; Abdullahi A.
The study was carried out to assess the properties of High-strength concrete made using Quarry dust as Fine aggregate. Preliminary tests were carried out on the aggregates to determine their suitability for use in High- strength concrete. The aggregates were well graded and other properties met the requirements of aggregates to be used for High-strength concrete. Superplasticizer and Rice husk were used as chemical and mineral additives to improve the workability and other properties of the concrete. Based on the properties of the aggregates, a mix ratio of 0.23:0.51:0.044:1.05:0.7:0.2, representing cement: fine aggregate: coarse aggregate: superplasticizer: water: rice husk was used. Concrete cubes of 100x100x100 mm were cast, cured and the 28-day compressive strength determined. An average 28-day compressive strength of 63 N/mm2 was obtained. This can be categorized as class I high strength concrete and is applicable in the construction of high rise buildings. The Study therefore concludes that quarry dust can be used as total replacement for fine river sand in high strength concrete production.
ASSESSMENT OF THE HYGROTHERMAL PROPERTIES OF MORTAR USING QUARRY DUST
(1st International Civil Engineering Conference (ICEC 2018), 2018-09-22) Okafor A.; YUSUF, Abdulazeez; Abdullahi A.
Assessment of the hygrothermal properties of mortar using quarry dust as fine aggregate was studied. The material used include Ordinary Portland Cement, water and quarry dust. Preliminary test such as particle size distribution, bulk density, moisture content and specific gravity were conducted on the aggregate in accordance to BS EN 1097:6. The mortar was prepared using a mix ratio of 1.4 and cured for 28 days. Water absorption, porosity and sorptivity test were the properties measured. Fineness modulus of 2.94, specific gravity of 2.42 and water absorption of 1.4% was recorded. The porosity and sorptivity were within the limit set by standard but the water absorption capacity was slightly higher that the limit specified. The study concluded that quarry dust can be used in the production of structural mortar.
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.