Investigative Study of Chicken Feather and Synthetic Hair Fibre on Mechanical and Microstructural Properties of Interlocking Concrete Block

Efforts have been made to improve the quality and performance of concrete structures especially its permeability and durability properties. Concrete is a heterogeneous material containing several components (sand, aggregate, cement, etc.) which vary in size and geometry, and their positions in the concrete enclosure are randomly distributed, giving them defects even before experiencing any form of mechanical loading. In this study, the compositions of Chicken Feather Fibre (CFF) and Synthetic Hair Fibre (SHF) by weight were varied by 0%, 1.5%, 2.5%, 3.5% and 5% for Samples A to E respectively. Physical and Mechanical properties such as water absorption (WA), thickness swelling (TS), compressive and split tensile strength were determined. Results showed that WA and TS property of the fibre reinforced concrete block decreased with decrease in percentage by weight of CFF and SHF and curing days with highest value being 10.01 to a lowest value of 0.14. Also, compressive strength (CS) for sample A increased with increase in curing days from 16.98MPa at 7 days to 20.66MPa at 28 days and sample B has its highest CS at 14 days with 9.98 MPa while other samples decreased progressively. Split Tensile Strength (STS) for sample A increases with increase in curing days from 9.84MPa to 13.64MPa while sample B decreases from 7 to 21 days of curing from 5.43MPa to 4.79MPa and increased at 28 days to 4.92MPa. Samples C, D and E follow same trend as sample B. The SEM study shows that the interlocking concrete block (ICB) containing 0% of chicken feather and synthetic hair fibre has brittle characteristics while other samples containing different percentage by weight of chicken feather and synthetic hair fibre shows ductile characteristics. CFF and SHF enhanced WA, TS, CS and STS of fibre reinforced concrete.

Impact of Bush Burning on Chemical Properties of Some Soil in Igboora, Oyo State, Nigeria

Soil is used in agriculture as an anchor and primary nutrient base for plants, and the types of soil and available moisture determine the species of plants that can be cultivated. Bush burning, whether as result of a wildfire or a controlled burning, affects not only the appearance of the landscape, but the quality of the soil. Bush burning method of land clearing is a traditional farming system used as a means of land clearing for crop production. This method of land clearing has both beneficial and detrimental effects on soil physical and chemical properties. Therefore, this study investigated the effects of bush burning on soil chemical properties at different soil depth of 0-30 cm and 30-60 cm respectively base on the rooting depth of crop planted. The experiment was carried out in six selected farms in Igboora, Ibarapa central Local Governmental, Oyo State. The soil sampled were collected from burnt and unburnt experimental soil and analyzed using USDA standard methods for soil analysis for the selected chemical characteristics (pH, Ca2+, Mg2+ Na+. TN and P). Two samples were taken from each burnt and un-burnt locations at depth of 0-30 and 30-60 cm. Paired t-test was used to compare means value of soil chemical properties determined from burnt and un-burnt soil. ANOVA was used for significance difference between soil from burnt and un-burnt soil. pH increased from moderately acidic to slightly acidic, phosphorus content of the soil increased greatly from un-burnt soil to burnt soil at 0-30 cm and 30-60 cm depths from 6.64 to 22.21 ppm and 3.53 to 24.95 ppm, respectively. Similarly, potassium increased from 0.27 to 0.40ppm at 0-30cm depth but decreased from 0.23 to 0.17 ppm at 30-60 cm depth. Nitrogen reduced at both depths from 0.80 to 0.76% and 0.72 to 0.68% respectively. Magnesium also increased from 1.3 cmol/kg to 2.00 cmol/kg and 1.65 to 1.75 cmol/kg at both 0-30 cm and 30-60 cm depth respectively. Whereas calcium showed a reduction from 3.17 to 2.85 cmol/kg and 1.65 to 1.45 cmol/kg at both depths. The variations observed between burnt and un-burnt soil for Ca, Mg, exchangeable acidity, pH, Nitrogen, potassium was significant at p<0.05 probability level. This indicates that bush burning has an impact on soil physical and chemical properties which may affect the suitability of the soil for crop production. Based on this, there is need for environmental education for farmers in the area in order to know the implications of bush burning on soil properties for soil sustainability which will boost food production.

Development of Fuzzy Based Autoregressive Moving Average Exogenous Input Model for Water Flow in Nigerian Kanji Hydro-Power Dam

Design of robust control system for any system requires model-driven approach. Therefore, it becomes imperative to develop a dynamic model suitable for controller design on safety operation of hydropower dam for power production in Kanji dam in Nigeria. Model for reservoir flow was developed in MATLAB environment using Fuzzy Based Autoregressive Moving Average Exogenous Input (FARMAX) model structure in this study. The data used for model development covered a period of ten years (2003-2013). It consists of water inflow (WI), water outflow (WO) and spillage (S). WI and S are input variables while WO was the output variable. The model obtained using the unsmoothed data with an outlier gave -14.115%, -0.302 and 610.317 for fit, R2 and RMSE, respectively. Unsmoothed data with no outlier gave -13.802%, -0.295 and 608.643 corresponding to fit, R2 and RMSE, respectively. The model obtained using the smoothed data in the presence of an outlier gave 80.533%, 0.962 and 104.113 for fit, R2 and RMSE, respectively. Smoothed data in the absence of outlier gave 81.533%, 0.962 and 99.637 for to fit, R2 and RMSE, respectively. FARMAX has the best fit value of 87.8774% when number of rules was equal to 3 with optima model order of 3 1 4 3. The model can serve as a decision support system in evaluating the optimal reservoir operation policies in real time.

Evaluation of Topsoil Competence, Aquifer Types, Groundwater Prospect and Flow Pattern using Geoelectric Characterization for Part of Ogbomoso, Nigeria

Part of Ogbomoso Southwestern Nigeria was assessed using electrical resistivity method with a view to obtaining the subsurface geoelectric parameters (resistivities and thicknesses), categorizes the topsoil into different competence zones and evaluates the aquifer types, groundwater prospect and flow pattern. Fifty-four Vertical Electrical Sounding (VES) data were quantitatively interpreted using the partial curve matching technique to obtain the preliminary layer parameters which were further refined through 1-D forward modelling WinResist software package. The resulting final layer parameters were used to generate 2D geoelectric sections, isopach and isoresistivity maps and subsequently used to categorize the study area into different topsoil Competence, Aquifer types and Groundwater Potential zones. Static water levels of hand-dug wells in the area were used to generate the groundwater flow pattern. Four subsurface geoelectric layers were delineated. These were the topsoil, laterite, weathered/partly weathered layer (main aquifer) and fractured/fresh bedrock. The resistivities and thicknesses of the layers were 76-1858, 649-2021, 17-880 and 260-33385 Ωm and 0.4-4, 0.7-1.9 and 1.9-25.2 m respectively. The groundwater flow pattern in the area was NE-SW. The study concluded that incompetent to highly competent topsoil, weathered bedrock (main) aquifer unit/partly weathered/fractured bedrock aquifer and generally low groundwater potential with NE-SW flow direction underlay the study area.

Effects of Hollow Sizes on the Properties of Sandcrete Blocks

Two-cell hollow sandcrete blocks constitute the dominant wall construction material for modern shelter in many African countries, especially Nigeria. The hollow cavities in the block have adverse effect on its mechanical characteristics. This study investigated the effects of hollow sizes on the properties of sandcrete blocks. Sandcrete blocks of size 225 × 225 × 450 mm with varying hollow sizes of 175 × 187.5, 173 ×190 and 180 × 210 mm and web thickness 25, 35 and 15 mm respectively; were produced using cement: sand ratio of 1:12. The blocks were tested for compressive strength, density and water absorption. The results indicated that compressive strength at 28 days for blocks with hollow sizes 175 × 187.5, 173 ×190 and 180 × 210 mm are 5.22, 3.64 and 0.41 Nmm-2 respectively. The corresponding densities are 2307.56, 2589.15 and 1715.23 kg/m³ while the rate of water absorption are 22.2, 18.8 and 24.5%, respectively. It was concluded that the larger the size of the hollow in sandcrete blocks the lower their mechanical properties.

Abuse of Parking Facilities and the Decay of Ikeja Central Business District, Ikeja Local Government Area, Lagos State

Illegal parking has been a topical issue in environmental planning and management, especially in the area of generating early warning systems for preparedness against space abuse. However, the concentration of research effort on accessibility in central business district with unjustified neglect of parking abuse impedes the search for analytical explanations and effective strategies to control spatial challenges. The study examined the types and nature of parking facilities and parking abuse. It also examined causes and effects of the abuse, as well as the response to abuse of the parking facilities in Ikeja Central Business District of Ikeja Local Government Area. Primary and secondary data were used for the study. Primary data were collected through in-depth interview with opinion leaders and questionnaires administered to 106 respondents randomly sampled in the core and periphery of the Central Business District of Ikeja. The data collected were analyzed using descriptive statistics such as frequency counts, percentage and chi-square. Secondary data used were map of the study area and images generated from Google earth. Results showed that there were two types of parking facilities; off-street (destination parking lot) and on-street parking facilities in the area. The nature of parking abuse was highly indiscriminate, and the prevailing type of parking facility abuse in the study area was unauthorized conversion of earmarked parking spaces to commercial trading spots. The effects of the parking abuse were mainly unavailability of parking space and traffic congestion, and the major perpetuators of the abuse were traders. The response of enforcement officials to indiscriminate parking was affirmed to be inefficient by 87.7% of the respondents. The study concluded that the abuse of parking facility was rampant in the study area.

Relationship Between Compressive Strength and Splitting Tensile Strength of Palm Kernel Shell Concrete

The use of palm kernel shell (PKS) has gained acceptance in the production of concrete. Compressive strength is the mostly used strength characteristics of concrete. The compressive strength CS of concrete should provide a good basis for predicting the splitting tensile strength STS. The aim of this study is to establish a mathematical relationship between the CS and STS of concrete produced with PKS. In this study, coarse aggregates was fully replaced with PKS at varying water-cement ratios (w/c) for concrete mix ratios 1:1½:3 and 1:2:4. Unit weigth of the PKS, slump, compressive and splitting tesnsile strength were determined. A relationship between CS and STS was developed for the different w/c ratios using exponential function aproximation. Physical property tests carried out on the PKS characterized it as lightweight aggregate with saturated surface dry unit weight of 1.27. The slump revealed that PKS concrete at 0.3 and 0.4 w/c is stiff and not workable. CS and STS at 28day for mix ratio of 1:1½:3 at w/c of 0.3, 0.4, 0.5 and 0.6 were respectively 3.2 and 1.2; 9.4 and 2.1; 10.8 and 2.6; 9.0 and 2.4 N/mm2. The corresponding values obtained for mix ratio 1:2:4 were 3.0 and 1.0, 1.7 and 1.3, 4.5 and 1.6, 7.7 and 1.9N/mm2, respectively. Equations relating CS and STS at 0.3, 0.4, 0.5 and 0.6 w/c were established. It was concluded that PKS concrete produced with mix ratios 1:1½:3 and 1:2:4 performed better in compression and splitting tensile strength at w/c of 0.5 and 0.6.

Urban Growth and Sustainable Development of the Built Environment in Abuja Metropolis

Rapid urban growth in the federal capital of Nigeria in the last two decades has more effect on the development changes that characterized the cosmopolitan city. This has put enormous pressure on the built environment, where urban construction and transformation are taking place. The paper assessed urban growth and sustainable development of the built environment in Abuja. Its causes and consequences were investigated with respect to five {5} districts that make up the metropolis. The approach to this research is urban environmental sustainability in defining developmental change patterns for quality of the built environment research is presented, and a number of key performance indicators variables were examined. Seventy five (75) questionnaires were distributed to purposive respondents and Sixty- nine (69), accounting for 92% of the number of distributed questionnaires were retrieved and employed for data analysis. The research collected data using a uni-variated analysis on 31 rated likert of a five-point scale. Using descriptive and inferential statistics techniques, the sum weighted score (SWS), mean weighted score (MWS) and Relative Importance Index (RII) rating was obtained. Four major findings were discovered. Firstly, the predominantly building development skyline were for commercial services (MWS= 3.88). Secondly the factor of change in urban growth revolves around public building use and redevelopment of residential properties involving Increase property/Rental Value (MWS= 3.68). Thirdly the major determinants of urban growth were identified as social, economic and spatial political factors as demolition of satellite settlement (MWS=3.35) and lastly non adherence to managerial practices of building regulations enforcement and it implementation in construction. The noticeable consequences had been planning regulation/ provision (MWS=3.14) among others. The study recommended that property developer and stakeholder should adhere to designated master plan implementation and control measures while policy makers should focus more on meeting contemporary urban challenges such as rapid urbanization, balance between economic development and urban sustainability as well as environmental change.

2D Electrical Resistivity Imaging of Bedrock Fissures in Ogbomoso, Southwestern Nigeria

2D electrical resistivity surveys were conducted around the site of the failed proposed Ogbomoso North Secretariat building with a view to examining the trend of suspected bedrock fissures and assessing the vulnerability of structures in the vicinity to potential failure. Electrical Resistivity Tomography data were acquired along ten traverses 80-200 m long each, using the dipole-dipole electrode configuration with station interval of 5 m and expansion factor, n, varied from 1 to 6. The data were processed by using 2D resistivity inversion technique in the DipproTM software package to generate 2D resistivity sections beneath the traverses. The 2D resistivity sections delineated 2-19 m thick typically clay overburden underlain by bedrock with resistivity ranging from 103 to 59767 Ωm, and anomalously low resistivity zones suspected to be fissures within the bedrock. The bedrock fissures are generally 5-20 m wide and occur at depths ranging from 5 m to ˃25 m beneath the traverses. The fissures trend southward toward the roundabout and front of the College of Health Sciences premises. The incessant road failures and groundwater seepages observed within the study area are attributable to the network of bedrock fissure.

A Time Series Analysis of the Trend of Crime Against Property in Oke-Ogun Region of Oyo State, Nigeria

Temporal variation in spatial crime occurrence has been a topical issue in environmental criminology and criminal justice research, especially in the area of generating early warning systems for preparedness against crime. However, the concentration of research effort on urban crime pattern with unjustified neglect of regional crime impedes the search for analytical explanations and effective strategies to eradicate crime. Hence, this study examined fluctuant pattern of property crime in Oke-Ogun region of Oyo State, Nigeria. It also assessed direction and incidence speed of the crime in the area. This is with a view to understanding the influence of changes in time (year factor) and other factors (a faulty system of education, erosion of traditional values, porous border, and unemployment among others). over property crime occurrence in the region. Crime reports were collated from the Nigerian Police records on nine typologies of property crime from 2005 to 2012. The geo-analytical techniques employed to examine temporal variations in crime were exponential trend smoothing technique with a smoothing constant of 0.3 and the least-squares trend analytical technique. Regression and correlation coefficients represented by “b” and “r” respectively were used to determine the changing rate of the crimes over the period of year under investigation. Analysis showed that out of the nine crime types that were analysed, three crimes were found to exhibit a rising trend with the effluxion of year while six exhibited a declining trend. Aggregately, crime against property had downward sloping trend lines. The negative values associated with (b = – 93.04, r = – 0.62) property crime confirmed the negative lapse rates and inverse relationships. The coefficient of determination (r2) in this case is 0.3969. However, the study concluded that 39.69% of variations in the level of property crime were influenced by changes in year and 60.31% was explained by other factors which included a faulty system of education, erosion of traditional values, porous border, and unemployment among others.