Civil & Environmental Engineering- Scholarly Publications

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    Open Access
    28-Day Strength Predicting Model for Foamed Aerated Concrete Containing Pulverized Bone as a Partial Replacement of Cement
    (International Association of Scientific Innovation and Research (IASIR), USA, 2013-09) Ikponmwosa, E; Falade, F; Fapohunda, C
    This paper presents the results of a mathematical model developed for predicting the 28-day compressive strength of foamed aerated concrete containing pulverised bone as partial replacement of cement for the purpose of quality controls. Strength-porosity relation was used as a basis for the development of the model, and the Bisection Methods of Numerical analysis was used to evaluate the inherent constants. For all the percentages of cement replacement with pulverised bone, the experimental strength values compare well with those of the model. It can thus be concluded that the model is valid for foamed aerated concrete with and without pulverized bone. The model has been validated up to 20% replacement of cement with pulverised bone.
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    Open Access
    African Regional Conference on Engineering Education:
    (2004) Falade, F.
    The African Regional Conference on Engineering Education (ARCEE) provides a forum for all the stakeholders in engineering and technology education within the region to come together and deliberate on common problems within the compass of engineering and technology and proffering solutions to them. We have had two meetings in Lagos, Nigeria (2002 and 2004). During ARCEE 2002, it was decided that the programme be held biennially and to be rotated among the member nations while in 2004 an action plan was drawn up and strategies were mapped out for its implementation. The details of the action plan are presented in this paper. The third meeting tagged 'ARCEE 2006' is to be held in Pretoria, South Africa.
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    Open Access
    Ameliorating Traffic Congestion and Impact on Climate Change with Park and Ride Transport
    (Covenant University, 2017) Rikho, J.; Ndambuki, J.; Kupolati, W.; Adeboje, A.; Kambole, C.
    Traffic congestion occur as more vehicles ply the road and result in reduced travel speed, increased travel time, unnecessary queuing, obstruction on travel path and impediment to traffic flow. Thirteen per cent of greenhouse gases (GHG) emitted are caused by the transportation system which continues to grow. Fume emanating from vehicles contributes greatly to the emission of GHG. Park and Ride was investigated within the Central Business District (CBD) of Tshwane with a view to improving the traffic congestion and reducing the effects of GHG on the climate. Traffic counts and questionnaires distribution were done on the major access routes to the CBD. The quantities of carbon dioxide (CO2) emitted by traffic and that would be reduced when park and ride system is implemented in the City of Tshwane Metropolitan Municipality (CTMM) were determined. Results of traffic volume counts showed high dependence of more than 70% of people on passenger cars as the mode of transit within the study area. It also revealed that almost 89% of the interviewed population are delayed by traffic, on their way to the work place in the morning. Fifty-four per cent of the people interviewed showed readiness to utilize the park and ride facility if their safety and security would be guaranteed. Furthermore the study showed that 96.2% of CO2 emitted could be reduced by the implementation of the park and ride system on the A Re Yeng BRT and also in the major cities of Tshwane.
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    Open Access
    Analysis of pollution status of River Illo, Ota, Nigeria.
    (Springer, 2008) Longe, E.O.; Omole, D.O.
    An assessment of the pollution status of River Illo, located within River Owo catchments area in Ota, Ogun State, Nigeria, was carried out. The River’s response to de-oxygenation due to BOD loading from an abattoir and its dissolved oxygen (DO) level was predicted using the modified Streeter-Phelps model. The average concentrations of measured parameters at the sampling stations include: 2.24 mg/l of DO, 312.85 mg/l of BOD, 782.86 mg/l of chemical oxygen demand, and 620.76 g/l of total solids. The DO model for River Illo showed a positive correlation between measured and calculated DO, while the dissolved oxygen curve gave a double spoon shape of two major segments with distinct zones of degradation, decomposition, and recovery. The self-purification factor (f) for both segments ranged between 0.8 and 1.1 depicting River Illo as a slow moving or sluggish river. The above results revealed slow re-aeration of the water body while full recovery from pollution was difficult. The treatment of River Illo before usage is very essential to ensure public health safety of users from waterborne diseases.
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    Open Access
    Appraisal of water supply facilities in rural riverine coastal areas of Lagos State
    (J. of Sustainable Developt in Africa, Clarion University, Pennsylvania, 2009) Longe, E.O.; Omotoso, O.B.; Sodamade, G.A.
    The paper appraised water supply facilities in the rural riverine coastal areas of Lagos State. Inadequate water supply in quantity and quality characterised the communities. Water supply through boreholes fitted with hand pumps was seen as a reliable and sustainable water supply for the communities. Community level participation in management of facilities was seen to enhance improvement in water supply in quantity and quality.
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    Open Access
    An Approach to Re-aeration Coefficient Modeling in Local surface water quality monitoring
    (Environmental Modelling and Assessment, 2013) Omole, D.O.; Longe, E.O.; Musa, A.G.
    Re-aeration coefficient (k2) for River Atuwara, Ogun State, Nigeria was calculated from dissolved oxygen and biochemical oxygen demand data collected over period of 3 months covering the two prevailing climatic seasons in the country. Both the Akaike and Bayesian information criteria were used in the selection and analysis of ten models to identify the most suitable re-aeration coefficient (k2) model for Atuwara River. Models that passed the confidence limit were subjected to model evaluation using measures of agreement between observed and predicted data such as percent bias, Nash–Sutcliffe efficiency, and root mean square observation standard deviation ratio. The used approach yield better results than empirical models developed for local conditions while it is also useful in conserving scarce resources.
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    Open Access
    Assessing the safety of drinking water sources in Ado-Odo/Ota Local Government Area, Ogun State, Nigeria. Nigeria.
    (Faculty of Engineering, University of Lagos, Lagos, 2012) Longe, E.O.; Omole, D.O.; Mgbachi, C.S.
    This study investigated the sources and quality of domestic water supply to 124 households in 16 communities of Ado-Odo/Ota Local Government Area of Ogun State, Nigeria. In order to achieve the set objective, field surveys .as well as administration of questionnaires were carried out while ten water samples from three different water supply sources were collected and analyzed for various water quality variables of interest. The field survey was carried out between April and May 2009. From survey results, surface and groundwater are the two major water supply sources in the investigated area. On coverage level, only 1.6% of the sampled population is serviced by pipe borne water from the state water works while 79.1% and 17.7% obtain their domestic water supply from groundwater and surface water sources respectively. The remaining 1.6% of the sampled population is serviced by private water vendors. Laboratory results show that water from all the sources investigated is generally slightly acidic, while levels of cadmium were higher than the Nigerian Standard for Drinking Water quality limit of O.003mg/l specified for potable water supply. The results of chemical and microbiological analyses also reveal impairments in quality of River Atuwara, a major source of domestic water supply and intake for the state public water work with high levels of Pb, Ni and Total Coliform. The water quality status of the various sources of domestic and public water supply in the surveyed area is unsafe and thus poses health concerns to users if well treated.
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    Open Access
    Assessment of onsite Wastewater treatment in Urban Coastal Area of Lagos Island, Lagos State, Nigeria
    (Faculty of Engineering, University of Lagos, Lagos, 2020) Sodamade, G.A.; Longe, E.O.; Balogun-Adeleye, R.M.
    This paper assessed the effectiveness of onsite waste water treatment in urban coastal environment of Lagos. The major technical problem has to do with the effectiveness and performance of such a technology in areas of high water table.
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    Open Access
    Assessment of road accidents in Nigeria (a case study of Lagos-Ibadan Expressway)
    (Nigerian society of Engineer, 2013-06) Adeboje, A.O.; Olutaiwo, A.O.; Adedimila, A.S.
    Lagos-Ibadan Expressway is infamous for high accident rate, leading to loss of innocent lives. The contributions of human, road, vehicle and environmental factors to these road accidents were examined. A comprehensive questionnaire was distributed to one hundred (100) respondents (drivers, passengers, health workers, federal road safety officers, passengers and students of tertiary institutions, to obtain their views on accidents. Official reports on road accidents were obtained from LUTH, UCH and FRSC and subjected to statistical analyses. It was established that the human factors (nonchalant attitude of drivers, distractions from passengers and carelessness of pedestrians) among others, contribute most to accident followed by road factor, then vehicle factor while the environmental factor contributes least. Analysis also shows that at least one (1) person is killed; at least 3 people are injured out of at least 6 people involved in a single accident on the Lagos - Ibadan Expressway.
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    Open Access
    Assessment of Steel Slag as Replacement for Coarse Aggregate in Concrete: A Review
    (Faculty Engineering Hunedoara, 2018) Adedokun S.I; Anifowose M.A; Odeyemi S.O
    This study presents a review on the utilization of steel slag as replacement for coarse aggregate in concrete. Merits and demerits of steel slag in concrete as well as its physical properties and chemical compositions of steel slag are also presented. It has been reported that it is economical to use steel slag, as the costs of steel slag are just about 50% of that of conventional aggregates. However, the optimum replacement of coarse aggregate with steel slag that gives better mechanical properties (compressive strength, tensile strength and flexural strength) than conventional concrete is found to be between 30 and 60%. In South Western part of Nigeria, there are numbers of steel/iron producing company with large deposits of steel slag. Therefore, there is need for the utilization of this by-product (steel slag) in concrete production in Nigeria as cost of natural aggregates (fine and coarse aggregate) is becoming higher.
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    Open Access
    An assessment of the impact of abattoir effluents on River Illo, Ota, Nigeria
    (Asian Network for Scientific Information, 2008) Omole, D.O.; Longe, E.O.
    A waste management paper on generation and mamanement of abattoir waste products. It also investigated the effects of the waste products on the quality of Illo River
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    Open Access
    Assessment of wastewater discharge impact from a sewage treatment plant on Lagoon water, Lagos, Nigeria.
    (Maxwell Scientific Organisation, 2010) Longe, E.O.; Ogundipe, A.O.
    An assessment of wastewater discharge impact from the University of Lagos treatment plant on lagoon water. The sink has been greatly polluted.
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    Open Access
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    Open Access
    Basic oxygen furnace slag for road pavements: A review of material characteristics and performance for effective utilisation in southern Africa
    (Elsevier, 2017-05) Kambole, C.; Paige-Green, P.; Kupolati, W.K.; Ndambuki, J.M.; Adeboje, A.O.
    Basic oxygen furnace (BOF) slag aggregates exhibit several favourable technical and environmental characteristics compared with natural stone aggregates, making them potentially valuable road construction materials. BOF slag-bitumen mixes have shown better resilient moduli, rutting resistance, bonding and moisture damage resistance and stripping resistance than mixes with natural aggregates and they can also be high quality substitutes for natural aggregate in lower road pavement layers. Regrettably, most southern African specifications do not cater for slags resulting in limited BOF slag reuse hitherto. This may be due to observed pavement performance problems arising from some chemical constituents in this slag. Excessive free lime (f-CaO) and periclase (MgO) in slags react with water, resulting in large volume expansions which can lead to premature failure when used in roads. Aging treatment hydrates these oxides, thus ensuring allowable slag expansion. Low C3S and C2S contents in BOF slag make it a poor hydraulic binder. It may nonetheless, be used in soil stabilisation when activated by lime and other pozzolans. Heavy metals such as chromium, vanadium and nickel in the slag could potentially leach and pollute the environment. Assessment and monitoring of such elements are necessary for the environmental acceptance of using BOF slag in road pavements.
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    Open Access
    Behaviour And Analysis Of Bamboo Reinforced Concrete Beams Under Flexural Loading.
    (2002) Falade, F.; Akeju, T.A.I.
    In this study, the behaviour of bamboo reinforced concrete beams was examined under a third point loading. Each beam was simply supported over an effective span of 600mm. The results showed that the behaviour of the beams was governed by the strengths, moduli of elasticity and stress-strain relationship of its components (reinforcement and concrete). Bamboo reinforced beams exhibited enhanced cracking and failure strengths when compared to the equivalent in plain concrete. There was increase in first-cracking and post-cracking strengths for beams with increase in bamboo content and curing age. A comparison of stress-strain distribution in the beam at different percentages of reinforcement indicates an optimum of 5.20% of cross sectional area of the beam for bamboo in bamboo reinforced concrete beams.
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    Open Access
    Behaviour Laterized Concrete Beams Under Moment And Shear.
    (1991-02-21) Falade, F.
    Abstract: The science and technique of substituting laterite for fine aggregate ill normal concrete work is rapidly increasing ill Nigeria. Studies Oil laterized concrete elements have been devoted primarily to observation under unit actions like the cube strength, split tensile strength, modulus 0/ rupture and creep characteristics. The present report gives the results of twenty four reinforced-laterized concrete beams, they were tested under combined actions of moment and shear. The principal variable are the mix proportions, percentage tensile reinforcement and shear span 10 effective depth ratio (aid). The results showed that the higher the percentage tensile reinforcement and cement or aggregate ratio the higher the shear and moment capacities 0/ the beams. When the shear span to effective depth ratio was increased, the shear capacity of the beams decreased while moment capacity increased. The shear span to effective depth ratio is the single most important factor that influences the mode of failure of the laterited concrete beams
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    Open Access
    Behaviour of Axially Loaded Bamboo Reinforced Concrete Columns
    (Devon Science Company, 2008) Falade, F; Ikponmwosa, E
    This paper reports on the behaviour of bamboo reinforced concrete columns under the applied axial loads. 150x150x1000mm columns were cast using 1:2:4 mix with water/cement ratio of 0.65. The bamboo content was varied from 0% to 2.5% of the cross sectional area at interval of 0.5%. 10 x 10mm bamboo splints were used. The surface of the bamboo splints were coated with bituminous paint and sand blasted to improve its bond characteristics. 8mm diameter bar links were provided at 150mm centers with their ends tied with binding wires. The specimens were cured in water at a temperature of 21o 1oC and tested at the curing ages of 7, 14 and 28 days. The results show that at 7-day curing age, the theoretical failure loads of bamboo reinforced columns increased when compared to that of un-reinforced specimens. At 1% reinforcement content, the theoretical failure load capacity at 7-day curing age is 8.52 N/mm2. The results are 9.01, 9.71, and 10.26N/mm2 for 1.5%, 2.0% and 2.5% bamboo reinforcement content respectively at the same curing age. When compared with un-reinforced specimens this showed an increase in strength values of 10.54, 16.88, 25.92 and 33.07% respectively. For the experimental failure loads of tested specimens, it was observed that with the introduction of bamboo reinforcement, the experimental failure loads decreased with increase in reinforcement when compared with un-reinforced specimens. For 1.0, 1.5, 2.0, 2.5% reinforcement, the experimental failure loads were 8.74, 8.12, 7.40, and 6.88 N/mm2 respectively. Compared to 0% reinforced specimen with experimental failure load of 9.56N/mm2, this showed a decrease in load carrying capacity of 8.53, 15.04, 23.10 and 27.91 percent respectively. This trend of decrease in failure load with increase in proportion of reinforcement is the same for specimens’ tested at other curing ages. The results theoretically show increase in strength with increase in reinforcement content at all ages. The deflection of the reinforced concrete columns decreased with age and increased with the percentage of bamboo contents in the columns.
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    Open Access
    Behaviour of Laterized Concrete Beams under Moment and Shear
    (1991) Falade, F
    The science and technique of substituting laterite for fine aggregate ill normal concrete work is rapidly increasing ill Nigeria. Studies Oil laterized concrete elements have been devoted primarily to observation under unit actions like the cube strength, split tensile strength, modulus 0/ rupture and creep characteristics. The present report gives the results of twenty four reinforced-laterized concrete beams, they were tested under combined actions of moment and shear. The principal variable are the mix proportions, percentage tensile reinforcement and shear span 10 effective depth ratio (aid). The results showed that the higher the percentage tensile reinforcement and cement or aggregate ratio the higher the shear and moment capacities 0/ the beams. When the shear span to effective depth ratio was increased, the shear capacity of the beams decreased while moment capacity increased. The shear span to effective depth ratio is the single most important factor that influences the mode of failure of the laterited concrete beams.
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    Open Access
    Behaviour Of Lightweight Concrete Containing Periwinkle Shells At Elevated Temperature.
    (School of Engineering, Taylor's University, Subang Jaya, Selangor, Malaysia., 2010) Falade, F.; Ikponmwosa, E.E.; Ojediran, N.I.
    This study presents the results of the investigation of the response of lightweight concrete to elevated temperature. Available literature indicates that research works have not been carried out in this area. The variables are: mix proportion, water/cement ratio, curing age and temperature. The parameters that were measured are: compressive strength, density and bond characteristics of the concrete matrix. The results showed that the compressive strength of concrete decreased with increase in water/cement ratio and temperature but increased with increase in curing age and cement content while the density decreased with increase in temperature. The bond between the concrete matrix also decreased as the temperature increased. Lightweight concrete containing periwinkle shells is only suitable for structures that will be subjected to temperature less than 300C
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    Open Access
    Characterization and Mathematical Modeling of Chloride Diffusion in Lagos Coastal Waters.
    (Springer, 2010-06) Akindahunsi, A.A.; Falade, F.A.; Afolayan, J.O.; Oke, I.A.
    Reports and news on failure due to corrosion degradation of structures ill aggressive environments are common occurrences in literature nowadays. This paper presents deterioration pattern of concrete structures in a coastal environment and effects chloride concentration on the steel reinforcements in concrete as a way towards failure control: water samples were collected from coastal environments (Tin Can Island and Bar Beach, Lagos, Nigeria). Laboratory analyses were carried out to determine the chloride contents and values obtained for the chloride concentrations were used to prepare different concentrations of chloride solutions to be used as aggressive curing environments. The test blocks were connected in parallel to a D.C rectifier set at 10 V to accentuate the rate of corrosion. A Half-Cell potential apparatus was used to determine the corrosion potential at intervals of 4 days for a period of 2R days after the initial 28 days of curing. A simple statistical model that relates chloride concentrations to the strength of the concretes was developed and tested. The study revealed that chloride concentration has significant effect on reinforcement. Rebar in 24878.80 mg/L curing tank was the most affected by corrosion with potential reading of -16(1.50mV and the rebar in this block wax nut able to sustain any tenxiIe load. The model developed described the strength of the concretes with correlation coefficient /?2 higher than 0.950 (R2 > 0.950)