Papers by Abbagana Mohammed
Path of Science
Concrete has low tensile strength, narrow ductile range and low crack resistance. Micro cracks in... more Concrete has low tensile strength, narrow ductile range and low crack resistance. Micro cracks in the concrete propagate quickly under loading, leading to brittle behaviour of the concrete. These cracks expose steel reinforcement to agents of corrosion. Adding steel fibres reduces the damage, but over a long period, the steel fibres corrode. This study used waste copper wire as fibre reinforcement in concrete to investigate the relationship between compressive, flexural and split tensile strengths. Grade 25 concrete was produced and cured for 7, 14 and 28 days before testing. One millimetre in diameter copper wire was used in the study. The fibre volume used was 0.5, 1.0 and 1.5%, respectively. The samples were tested for compressive, flexural and split tensile strengths. The results indicated a general increase in compressive, flexural and split tensile strengths of the concrete with an increase in waste copper wire fibre contents. Maximum compressive strength of 34.58 N/mm 2 was obtained at 1.5% fibre content and 28 days of curing. Flexural strength increases from 4.36 N/mm 2 at 0% fibre content and seven days curing to 6.68 N/mm 2 at 1.5% fibre content and 28 days curing. The split tensile strength increased fibre content from 2.72 N/mm 2 at seven days to 4.39 N/mm 2 at 28 days of curing. Mathematical models were produced for the relationships between compressive, flexural and split tensile strengths. The models have R 2 values greater than 70%, and the higher the value of R 2 , the better the model fits the data. This indicates that the model's predictors influenced the variations in the responses.
In current practice, the predictive analysis of stochastic problems encompasses a variety of stat... more In current practice, the predictive analysis of stochastic problems encompasses a variety of statistical techniques from modeling, machine, and data mining that analyse current and historical facts to make predictions about future. Therefore, this research uses an AR Model whose codes are incorporated in the MATLAB software to predict possible aero-elastic effects of Lekki Bridge based on its existing parametric data and the conditions around the bridge. It was seen that, the fluctuating components of the wind velocity as displayed by the fluctuant curve will result in the vibration of the structure, even strengthening the resonance effect of the structure. Therefore, it suggested that, the natural frequency of the bridge should be set aside far from system frequency considering direct parametric excitation of pedestrian or vehicular traffic speed.
Embodied Energy and Carbon IV Oxide Emission Analyses of Sandcrete Blocks and Compressed Earth Bricks Houses
This study analyzes the Embodied Energy (EE) and Carbon IV Oxide (CO2) emission of Sandcrete Bloc... more This study analyzes the Embodied Energy (EE) and Carbon IV Oxide (CO2) emission of Sandcrete Blocks (SCB) and Compressed Earth Bricks (CEB) houses. Energy and CO2 are emitted in the process of manufacture, transportation and construction of buildings materials. These energies and carbon dioxide are embodied in the materials. Thus, an exploratory research method was used to assess the EE and CO2 emission impacts of building materials for the two types of houses in Nigeria. A detailed inventory analysis approach was used with EE and CO2 emission factors obtained from Inventory of Carbon and Energy (ICE) database. The findings revealed the EE and CO2 emission for the CEB are 436,343.49MJ (2,288.59 MJ/m2) and 30,821.09 KgCO2 (161.65 KgCO2/m2) while for the SCB house are 632,298.58 MJ (3,316.37 MJ/m2) and 52,897.82 KgCO2 (277.45 KgCO2/m2) respectively. Thus, the SCB house expends 30.99% more EE and emits 41.73% more embodied CO2 than CEB. The comparison revealed that the CEB house is mor...
Effects of Waste Glass (WG) on the Strength Characteristics of Cement Stabilized Expansive Soil
The study investigates the suitability of using waste glass (WG) as admixture to cement stabilize... more The study investigates the suitability of using waste glass (WG) as admixture to cement stabilized black cotton soil (BCS) for roads, fills and embankment. The soil was classified as A-7-5 and CH according to the American Association of State Highway and Transport Officials (AASHTO) and the Unified Soil Classification System (USCS) Classifications. Chemical analysis revealed that WG is rich in main oxides such as Silicon Oxide (69.2), Aluminium Oxide (2.29), Iron Oxide (1.57), Calcium Oxide (15.1) and Sodium Oxide (8.75). The soil was stabilized with 0, 2, 4, 6 and 8% cement and 0, 5 10, 15 and 20% WG by weight of the dry soil. Laboratory tests were carried out using the Standard Proctor (SP) compactive efforts, California Bearing Ratio (CBR), Unconfined Compressive Strength (UCS), and compaction characteristics tests to evaluate the effectiveness of WG on Ordinary Portland cement (OPC) stabilized BCS. The results obtained showed a decrease in the plasticity index (PI), liquid limit...
Compressive Strength Testing of Plastered Straw Bale
This paper is a presentation of compressive strength testresults on plastered straw bale block. G... more This paper is a presentation of compressive strength testresults on plastered straw bale block. Guinea corn – straw fiber were baled and plastered with mortar into straw bale blocks of fibers with an average of 6mm thickness, 11.2% moisture content, and baled at a density of range between 0.161 - 0.190 kg/ mm 2 . The fiber blocks were subjected to vertical loading on different plaster thickness of 10, 15 and 20mm using 1:3, 1:4 and 1:6 mix proportion of cement to sand. The results showed that the maximum compressive strength of 6.046 N/mm 2 was obtained with amix ratio 1:3 and 20mm plaster thickness, while the minimum compressive strength of 1.698 N/mm 2 was obtained with a 10mm plaster thickness which meet the requirement of standard compressive strength of sand Crete block (1.8 - 2.5 N/mm 2 ) stipulated by the British standard (BS 6073).
In current practice, the predictive analysis of stochastic problems encompasses a variety of stat... more In current practice, the predictive analysis of stochastic problems encompasses a variety of statistical techniques from modeling, machine, and data mining that analyse current and historical facts to make predictions about future. Therefore, this research uses an AR Model whose codes are incorporated in the MATLAB software to predict possible aero-elastic effects of Lekki Bridge based on its existing parametric data and the conditions around the bridge. It was seen that, the fluctuating components of the wind velocity as displayed by the fluctuant curve will result in the vibration of the structure, even strengthening the resonance effect of the structure. Therefore, it suggested that, the natural frequency of the bridge should be set aside far from system frequency considering direct parametric excitation of pedestrian or vehicular traffic speed.
Embodied Energy and Carbon IV Oxide Emission Analyses of Sandcrete Blocks and Compressed Earth Bricks Houses
This study analyzes the Embodied Energy (EE) and Carbon IV Oxide (CO2) emission of Sandcrete Bloc... more This study analyzes the Embodied Energy (EE) and Carbon IV Oxide (CO2) emission of Sandcrete Blocks (SCB) and Compressed Earth Bricks (CEB) houses. Energy and CO2 are emitted in the process of manufacture, transportation and construction of buildings materials. These energies and carbon dioxide are embodied in the materials. Thus, an exploratory research method was used to assess the EE and CO2 emission impacts of building materials for the two types of houses in Nigeria. A detailed inventory analysis approach was used with EE and CO2 emission factors obtained from Inventory of Carbon and Energy (ICE) database. The findings revealed the EE and CO2 emission for the CEB are 436,343.49MJ (2,288.59 MJ/m2) and 30,821.09 KgCO2 (161.65 KgCO2/m2) while for the SCB house are 632,298.58 MJ (3,316.37 MJ/m2) and 52,897.82 KgCO2 (277.45 KgCO2/m2) respectively. Thus, the SCB house expends 30.99% more EE and emits 41.73% more embodied CO2 than CEB. The comparison revealed that the CEB house is mor...
Effects of Waste Glass (WG) on the Strength Characteristics of Cement Stabilized Expansive Soil
The study investigates the suitability of using waste glass (WG) as admixture to cement stabilize... more The study investigates the suitability of using waste glass (WG) as admixture to cement stabilized black cotton soil (BCS) for roads, fills and embankment. The soil was classified as A-7-5 and CH according to the American Association of State Highway and Transport Officials (AASHTO) and the Unified Soil Classification System (USCS) Classifications. Chemical analysis revealed that WG is rich in main oxides such as Silicon Oxide (69.2), Aluminium Oxide (2.29), Iron Oxide (1.57), Calcium Oxide (15.1) and Sodium Oxide (8.75). The soil was stabilized with 0, 2, 4, 6 and 8% cement and 0, 5 10, 15 and 20% WG by weight of the dry soil. Laboratory tests were carried out using the Standard Proctor (SP) compactive efforts, California Bearing Ratio (CBR), Unconfined Compressive Strength (UCS), and compaction characteristics tests to evaluate the effectiveness of WG on Ordinary Portland cement (OPC) stabilized BCS. The results obtained showed a decrease in the plasticity index (PI), liquid limit...
Compressive Strength Testing of Plastered Straw Bale
This paper is a presentation of compressive strength testresults on plastered straw bale block. G... more This paper is a presentation of compressive strength testresults on plastered straw bale block. Guinea corn – straw fiber were baled and plastered with mortar into straw bale blocks of fibers with an average of 6mm thickness, 11.2% moisture content, and baled at a density of range between 0.161 - 0.190 kg/ mm 2 . The fiber blocks were subjected to vertical loading on different plaster thickness of 10, 15 and 20mm using 1:3, 1:4 and 1:6 mix proportion of cement to sand. The results showed that the maximum compressive strength of 6.046 N/mm 2 was obtained with amix ratio 1:3 and 20mm plaster thickness, while the minimum compressive strength of 1.698 N/mm 2 was obtained with a 10mm plaster thickness which meet the requirement of standard compressive strength of sand Crete block (1.8 - 2.5 N/mm 2 ) stipulated by the British standard (BS 6073).
Open Journal of Civil Engineering, 2018
This paper reports a validation study involving sixth scale masonry model to replicate prototype ... more This paper reports a validation study involving sixth scale masonry model to replicate prototype tests carried out on five unit high masonry prisms. In order to test the applicability of small masonry models to real life problems, an investigation into masonry behaviour relevant to the serviceability requirement of masonry arch bridges was chosen as prototype test to validate the small scale masonry tests. Only representative masonry specimens were considered in the study; this corresponded to parts of an arch ring in a complete masonry arch. Two mortar designations; designation iv and designation v were used. These weak mortars tend to conform better to existing old structures. Loads were applied at four eccentricities of 0, 5, 9, and 14 mm from the centre of the specimens. This corresponds to e/d ratios of 0, 0.14, 0.25, and 0.39, where e is the eccentricity of the load and d the length of the transverse section of the specimens. The result shows that validation study corresponds with prototype study for low eccentricities; therefore, strength enhancement is seen over the concentric compressive strength. However, this does not apply at higher eccentricities as specimens were noticed to fail by elastic instability characterised by tension debonding of the top mortar joint.
Open Journal of Civil Engineering, 2018
This paper reports a validation study involving sixth scale masonry model to replicate prototype ... more This paper reports a validation study involving sixth scale masonry model to replicate prototype tests carried out on five unit high masonry prisms. In order to test the applicability of small masonry models to real life problems, an investigation into masonry behaviour relevant to the serviceability requirement of masonry arch bridges was chosen as prototype test to validate the small scale masonry tests. Only representative masonry specimens were considered in the study; this corresponded to parts of an arch ring in a complete masonry arch. Two mortar designations; designation iv and designation v were used. These weak mortars tend to conform better to existing old structures. Loads were applied at four eccentricities of 0, 5, 9, and 14 mm from the centre of the specimens. This corresponds to e/d ratios of 0, 0.14, 0.25, and 0.39, where e is the eccentricity of the load and d the length of the transverse section of the specimens. The result shows that validation study corresponds with prototype study for low eccentricities; therefore, strength enhancement is seen over the concentric compressive strength. However, this does not apply at higher eccentricities as specimens were noticed to fail by elastic instability characterised by tension debonding of the top mortar joint.
IOSR Journal of Mechanical and Civil Engineering, 2016
A laboratory study on the influence of modified proctor (MP) and standard proctor (SP) compactive... more A laboratory study on the influence of modified proctor (MP) and standard proctor (SP) compactive effort on expansive black cotton soil (BCS) specimens treated with up to 8% ordinary Portland cement (OPC) admixed with up to 20% waste glass (WG) by dry weight of soil were undertaken. The soil was classified as A-7-5(13) and CH according to the American Association of State Highway and Transport Officials (AASHTO) and the Unified Soil Classification System (USCS) Classifications. Chemical analysis revealed that WG is rich in main oxides such as Silicon Oxide (69.2%), Aluminium Oxide (2.29%), Iron Oxide (1.57%), Calcium Oxide (15.1%) and Sodium Oxide (8.75%). The soil was stabilized with 0, 2, 4, 6 and 8% cement and 0, 5 10, 15 and 20% WG by weight of the dry soil. The results obtained showed an increase in maximum dry density (MDD) with increase in WG content in all cement proportions used and as compared to the values obtained for the natural soil. The tests showed significant effects of the additives. The peak 7 days unconfined compressive strength (UCS) values of 1152 kN/m 2 and 1568 kN/m 2 were obtained at 8% OPC / 20% WG treatment for the SP and MP compactive efforts, respectively. These values are lower than the 1720 kN/m 2 recommended by Transport and Road Research Laboratory (TRRL) (1977) for adequate cement stabilization. The SP and MP compactive efforts at 28 days yielded UCS values of 1857 kN/m 2 and 2005 kN/m 2 which justified the slow pozzolanic reaction of WG when compared with cement hydration. CBR values were lower than the 180% criterion recommended by the Nigerian General Specifications (1997) for cement stabilized soil, however, specimens treated with 8% OPC/ (5-20%) WG and compacted at both energy levels met the requirement of 30% CBR specified by the Nigerian General Specification (1997) for sub-base in roads. Maximum improvement in CBR values of 55% and 65% for the entire blend was archived at 8% OPC/20%WG blend.
IOSR Journal of Mechanical and Civil Engineering, 2016
The cost of highway accidents in terms loss of lives, injuries and road closures is a major strai... more The cost of highway accidents in terms loss of lives, injuries and road closures is a major strain on the Nigerian economy. It has therefore become pertinent to explore the causes of such accidents from a road condition perspective with a view to limiting their frequency and degree of severity. Three federal roads in Bauchi State were considered for this study; Bauchi-Jos, Bauchi-Gombe and Bauchi-Yobe Border, respectively. The pavement condition data indicated that Bauchi-Jos rouate has the highest Road Condition Score (RCS) while Bauchi-Gombe route has the lowest RCS. The Jos route also accounted for the highest number of accidents and fatalities despite having the best pavement condition, while the Yobe route accounted for the least number of accidents and fatalities. The results support the general view that there is no strong correlation between pavement condition and traffic safety, however some design and planning issues like the degree of curvature of horizontal and vertical curves and number of towns/villages on the routes seem to play an important role in traffic safety.
IOSR Journal of Mechanical and Civil Engineering, 2015
Small scale modelling of structures is normally employed as a means to study the structural behav... more Small scale modelling of structures is normally employed as a means to study the structural behaviour of engineering structures in order to predict the real behaviour of such structures under various conditions of loading as well as under the influence of extreme weather events like flooding, earthquakes, severe wind storms etc. But in order to use small scale models to predict prototype behaviour, understanding is necessary of the effect of scale on such models. The fracture mechanics perspective of the effects of size on models is explored from available literature and its significance to reliable model studies is established in this review.
Biosystems Engineering, 2013
The objective was to make use of the combination of waste glass powder (GP) and rice husk ash (RH... more The objective was to make use of the combination of waste glass powder (GP) and rice husk ash (RHA) as replacement for Portland cement. Hybrid mixtures containing 0e20% GP and 0 e20% RHA were prepared. The best values of replacements by GP and RHA, based on the 28-days compressive strength and strength activity index, were determined as 10% and 5%, respectively. From these results, the properties of hybrid concrete tended to increase with age due to the development of higher pozzolanic activity. The results also revealed good evidence that both GP and RHA can be used together in concrete without any adverse effects.
Open Journal of Civil Engineering, 2015
Mortars provide the continuity required for the stability and exclusion of weather elements in ma... more Mortars provide the continuity required for the stability and exclusion of weather elements in masonry assemblies. But because of the heterogeneity of the mortar, its mechanism of behaviour under different load effects is dependent on the properties of the constituents of the mortar. The aim of paper is to determine the effect sand grading for various cement-sand-lime mortar designations (BS) and strength classes (EC) on the compressive strength and stiffness of mortar. Two silica sands; HST 95 and HST60 were used to make mortars in three strength classes: M2, M4 and M6, corresponding to mortar designations iv, iii and ii respectively. The results show that mortar made with the HST60 sand (coarser grading) usually resulted in mortar with a higher compressive strength and stiffness. The One Way ANOVA analysis of both compressive strength and stiffness at a significance level of 5% on the effect of sand grading on the two parameters also shows that they are both significant. There is also strong evidence of a linear correlation between the stiffness and compressive strength. The results indicate that in order to replicate full scale behaviour of masonry at model scales, the grading of fine aggregate in the models should be similar so as to properly model full scale behavior.
Mechanical Properties Of Concrete Containing Corn Cob Ash
Cement manufacture is energy intensive and contributes a considerable amount of CO 2 emissions in... more Cement manufacture is energy intensive and contributes a considerable amount of CO 2 emissions into the atmosphere. In this study, Corn cob ash (CCA) was used as the blending agent with cement in concrete. The experimental plan was designed to carry out compressive strength, flexural strength, density and water absorption tests on grade 30 concrete using 0, 5, 10, 15 and 20% CCA contents. The results indicated that compressive and flexural strength decreased with increase in CCA content and increased with curing period. The optimum blend was obtained at 10% CCA and 90% OPC contents with compressive and flexural strength values of 30.17 N/mm 2 and 5.64N/mm 2 at 90 days respectively. Concrete containing 20% CCA has water absorption of 1.80% at 90 days and this is 43.9% less than that of the control concrete. The density of concrete decreased from 2473 Kg/m 3 at 0% CCA content to 2397 Kg/m 3 at 20% CCA content.. MINITAB statistical software was used to carry out regression analysis and...
Embodied Energy and Carbon IV Oxide Emission Analyses of Sandcrete Blocks and Compressed Earth Bricks Houses
This study analyzes the Embodied Energy (EE) and Carbon IV Oxide (CO2) emission of Sandcrete Bloc... more This study analyzes the Embodied Energy (EE) and Carbon IV Oxide (CO2) emission of Sandcrete Blocks (SCB) and Compressed Earth Bricks (CEB) houses. Energy and CO2 are emitted in the process of manufacture, transportation and construction of buildings materials. These energies and carbon dioxide are embodied in the materials. Thus, an exploratory research method was used to assess the EE and CO2 emission impacts of building materials for the two types of houses in Nigeria. A detailed inventory analysis approach was used with EE and CO2 emission factors obtained from Inventory of Carbon and Energy (ICE) database. The findings revealed the EE and CO2 emission for the CEB are 436,343.49MJ (2,288.59 MJ/m2) and 30,821.09 KgCO2 (161.65 KgCO2/m2) while for the SCB house are 632,298.58 MJ (3,316.37 MJ/m2) and 52,897.82 KgCO2 (277.45 KgCO2/m2) respectively. Thus, the SCB house expends 30.99% more EE and emits 41.73% more embodied CO2 than CEB. The comparison revealed that the CEB house is mor...
This research predicts the strength properties of concrete containing Calcined Black Cotton Soil ... more This research predicts the strength properties of concrete containing Calcined Black Cotton Soil (CBCS) using response surface methodology. Cement production requires large amount of energy and emits greenhouse gases that have negative impact on the environment. Utilization of CBCS as cement replacement in concrete will reduce these negative impact. Experimental plan was designed using response surface method in Design Expert software to predict compressive strength, density and water absorption of concrete containing CBCS. The CBCS was varied from 5 to 20% while the curing period was varied and 7 to 28 days. Face-centered central composite design method of response surface was used. The design consists of two design factors at three levels (coded as -1, 0, +1) each. The factors are the curing period, and the CBCS contents. The results showed that CBCS is a pozzolana. CBCS increases durability of concrete by decreasing its water absorption. All the response surface models developed ...
Assessment of Embodied Energy and Carbon IV Oxide Emission of Concrete Containing Corncob Ash
International Journal of Sustainable and Green Energy, 2021
The purpose of this study is to assess the Embodied Energy (EE) and Carbon IV Oxide (CO2) emissio... more The purpose of this study is to assess the Embodied Energy (EE) and Carbon IV Oxide (CO2) emissions saving potentials of Corn Cob Ash (CCA) as partial replacement of Ordinary Portland Cement (OPC) in concrete. Cement manufacture is energy intensive and contributes considerable amount of CO2 emissions into the atmosphere. Globally, Concrete is the most consumed man-made material and about 95% of CO2 emissions from a cubic meter of concrete are from cement manufacturing. In this study, the experimental plan was designed to carry out compressive strength, flexural strength, density and water absorption tests on the concrete using 0, 5, 10, 15 and 20% CCA contents to replace OPC. Inventory method of analysis was used to determine the EE and CO2 emission for all the concrete mixes. The results indicated that the water absorption, density, compressive and flexural strength decreased with increase in CCA content and increased with curing period. The optimum blend was obtained at 10% CCA an...
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Papers by Abbagana Mohammed