Civil Engineering

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Civil Engineering

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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.
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
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.
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.
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.
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.
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
Structural Reliability Studies of Reinforced Concrete Beam subjected to Shearing forces with Natural Stone as Coarse Aggregate
(USEP: Journal of Research Information in Civil Engineering, 2019-02-12) Kolo, D. N.,; Aguwa, J. I.,; Tsado, T. Y.,; Abdullahi, M.,; Yakubu, D. M.,; Abubakar, M.
This paper presents experimental and structural reliability studies performed on Bida natural stones (BNS) used as coarse aggregate in concrete production. Construction activities based on these naturally occurring materials are major steps towards industrialisation and economic integration of developing countries like Nigeria. This explains the huge interest over the years in utilising such materials as substitute or partial replacement for concrete constituents. The method adopted to appraise the aim and objectives of the study was laboratory experimentation. A total of 80 concrete cubes of 150 mm × 150mm × 150 mm were cast and used for this study. First order reliability method (FORM) was employed to ascertain the level of safety of the beam. Sensitivity analysis was further conducted by varying the span, effective depth and area of shear reinforcement of the beam in shear. The result revealed that the reinforced concrete beam utilising Bida natural stones is structurally safe at a span of 3000 mm and 3250 mm for unwashed and washed Bida natural stones respectively with probabilities of failure of 1.07 × 10-3 and 1.14 × 10-3. Both unwashed and washed Bida natural stones were structurally safe at effective depth of 439 mm with probabilities of failure of 5.87 × 10-3 and 1.31 × 10-3in shear.
Top Cited Articles on Structural Engineering Reliability by the Nigerian Authors
(USEP: Journal of Research Information in Civil Engineering, 2020) Abubakar, Mahmud; Aguwa, J. I.; Abdullahi, M.; Sadiku, S.; Oritola, S. F.
This study analyses the characteristics of top-cited articles on structural reliability with at least one author affiliated to Nigeria. A search in the Google Scholar database for articles published between 2010 and 2020 was carried out. From the top-cited articles, variables related to the journal, article, and authors, such as journal ranking from SCImago Journals & Country Rank (SJR), H-index, author affiliations, international research collaboration, and source of funding were collected and descriptively analysed. A sample of 25 original reports was identified from the search. The average citations per year ranged between 0.10 and 6.1. The articles were published in 20 different journals (36% found in only four journals) with five of them based in Nigeria. It was observed, that international collaboration on reliability-based researches was present in 4% of the articles, and funding was reported in just 1 article. Articles having Nigerians as first authors were reported in 100% of the articles. Articles with authors affiliated to ABU, Zaria were more frequent in the sample. A list of top-cited articles is thus, presented to provide an overview of the top-cited articles. This study could aid in supporting further analyses regarding publication, citation behaviours, research funding and international collaboration of structural reliability based researches in Nigeria.
Reliability-Based Code Calibration in Civil Engineering: A Critical Review
(USEP: Journal of Science and Engineering Production, 2021) Abubakar, Mahmud; Aguwa, J. I.; Abdullahi, M.; Sadiku, S.
The use of new materials and the complexities in modern civil engineering infrastructures call for a systematic attempt to find accurate design solutions. It is clear that deterministic values are not reliable and that their use in the design of civil engineering structures can lead to instant failures. Thus, the use of the probability theory to determine the most reliable value of a parameter for the design of civil engineering structures is very relevant. This work is intended to review the literature on the application of probability theory in the calibration of civil engineering design codes. Consequently, to better evaluate designs and design details, it is important to understand the techniques as highlighted herein.
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.
Performance of Fly Ash-Based Inorganic Polymer Mortar with Petroleum Sludge Ash
(Polymers MDPI, 2021) Kankia, Usman Mubarak; Baloo, Lavania; Danlami, Nasiru; Bashar, S. Mohammed; Haruna, Sani; Abubakar, Mahmud; Jagaba, AhmadHussaini; Khalid, Sayed; Isyaka, Abdulkadir; Ibrahim, Umar Salihi
Petroleum sludge is a waste product resulting from petroleum industries and it is a major source of environmental pollution. Therefore, developing strategies aimed at reducing its environmental impact and enhance cleaner production are crucial for environmental mortar. Response surface methodology (RSM) was used in designing the experimental work. The variables considered were the amount of petroleum sludge ash (PSA) in weight percent and the ratio of sodium silicate to sodium hydroxide, while the concentration of sodium hydroxide was kept constant in the production of geopolymer mortar cured at a temperature of 60 °C for 20 h. The effects of PSA on density, compressive strength, flexural strength, water absorption, drying shrinkage, morphology, and pore size distribution were investigated. The addition of PSA in the mortar enhanced the mechanical properties significantly at an early age and 28 days of curing. Thus, PSA could be used as a precursor material in the production of geopolymer mortar for green construction sustainability. This study aimed to investigate the influence of PSA in geopolymer mortar.
Quality Assessment of Commercial Sandcrete Blocks in Minna Metropolis, Niger State
(Nigerian Journal of Technology, 2022) Abubakar, Mahmud; Omotoriogun, Victor
The spate of building collapse across the country over the years has raised questions about the quality of building materials and the need to investigate their suitability for construction. Sandcrete blocks are of interest been the most popular masonry unit widely employed in construction of walling units for building structures, hoardings of construction sites and foundations, in Nigeria. The aim of this study is to assess the quality of commercial Sandcrete blocks produced in Minna metropolis, Niger State, for compliance with existing standards: Nigerian Industrial Standard and Nigerian Building Code. The research was appraised through field surveys methods, sampling and laboratory experiments conducted on sixteen (16) selected block factories in Minna metropolis. A total of eighty (80) nine-inch blocks, five (5) each, were sampled from each factory and subjected to dimensional checks, water absorption and compressive strength tests. The results obtained from the laboratory experiments showed that the dimension, compressive strength and water absorption capacity of the sampled blocks were below standard specifications. The highlight of the field survey carried out showed discrepancies in the mix proportioning, curing practices and age of blocks utilized in the factories against those of the standards. Consequently, it was recommended that blocks produced in Minna should never be used for load bearing walls.
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.
Models to Predict the Fresh and Hardened Properties of Palm Kernel Shell Concrete
(Malaysian Journal of Civil Engineering, 2022-01-12) Kolo, D. N.; Tsado, T. Y.; Abbas, B. A.; Adamu, H. N.
Concrete is an assemblage of Cement, aggregates and water, the most frequently used fine aggregate for concrete production is sand sourced from river banks. The continuous exploitation of available granite conventionally used as coarse aggregate in concrete production coupled with rapid infrastructural development has resulted in its scarcity and often high cost. The suitability of utilising Palm Kernel Shell (PKS) as partial replacement for coarse aggregate in concrete production was examined in this paper. Preliminary tests were conducted on all aggregates to determine their suitability for concrete production. Concrete with 5, 10, 15, 20 and 25% PKS-coarse aggregate content was cast with a mix ratio of 1:2:4. The freshly prepared Palm Kernel Shell Concrete (PKSC) was cast in moulds measuring 150 x 150 x 150mm and cured using ponding method. The Compressive strength result shows that an increase in the PKS content results in a decrease in compressive strength of concrete. Linear regression models for the slump and compressive strength of the PKSC were developed and found to be sufficient in predicting the compressive strengths with R2 values of 96% and 92 % respectively.