39 research outputs found

    Evaluating the Quality Assurance and Control of Hot-Mix Asphalt from Selected Plants in South West, Nigeria

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    Roads are essential necessity of every nation and it is possible that even with proper designs, the roads might not be constructed to the design standard due to poor quality assurance and control resulting in poor pavement quality. This study presents experimental results carried out on various hot - mix asphalt (HMA) samples obtained across different Asphalt plants in South West Nigeria. This was done to determine the extent to which the HMA used in the construction and rehabilitation of Nigerian roads affect their service life. Six samples of the asphalt binder (bitumen) were obtained from each plant over a period of six months and tested. The tested properties were assessed based on the level of conformance with the specifications and requirements from the FMWH General Specification (Roads and Bridges). The results revealed that HMA from plant B had a specific gravity of 1.01, penetration of 65.00 mm, softening point of 53 oC, flash point of 237.00 oC, peak Marshall Stability of 18.25 kN, flow of 3.87 mm and voids in total mixture peak value of 5.08 %. HMA from plant E had a specific gravity of 1.03, penetration of 65.00 mm, softening point of 51 oC, flash point of 239.00 oC, peak marshall stability of 18.26 kN, flow of 3.67 mm and voids in total mixture peak value of 4.99 % and these were adjudged the best in conformance with the FMWH specifications. Adequate monitoring of HMA quality for either binder or wearing courses by carrying out quality control and assurance tests is thereby recommended as it affects pavement durability and performance. Keywords: Hot-mix asphalt, quality assurance, quality control, marshall stability, flow tes

    MECHANICAL STRENGTH DETERMINATION OF CRUSHED STONE AGGREGATE FRACTION FOR ROAD PAVEMENT CONSTRUCTION (CASE STUDY: SELECTED QUARRIES IN WESTERN NIGERIA)

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    In this research work, the mechanical strength of crushed stone aggregate fractions for road pavement construction in Western Nigeria was assessed. Samples of crushed stone aggregates were collected from nine (9) representative quarries spread across the states in Western Nigeria.The physical and mechanical properties of the aggregates were evaluated. The results were then compared with the specifications in international standards (BS and ASTM Standards). All the aggregate samples met the required limit for Loose Density, Water Absorption, Aggregate Crushing Value (ACV) and Aggregate Impact Value (AIV) tests. Aggregates samples from Samchase, Kopek, CCECC and SaliwaYetidipe quarries have flakiness indices exceeding the permissible limit (29.5%, 25.7%, 27.9% and 34.5% respectively). Hi-Tech and Western quarries samples have elongation indices of 44.5% and 40.3% respectively which are higher than the permissible limit. The two samples that failed Aggregate Abrasion Value test (AAV) are Hi-Tech and Western quarries, having 30.8% and 30.4% respectively. These two aggregates samples have AAV less than 35% which means they are still good for pavement construction only if the appropriate guidelines are followed (since any aggregate with AAV more than 35% is deemed weak for pavement construction). The study concluded that aggregates from Julius Berger quarry have the highest mechanical strength

    Design and Development of a Wear Testing Machine for Manufacturing Laboratories

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    Wear of parts during manufacturing processes is inevitable but controllable. Therefore, the critical study of wear in engineering components is vital because failure of components due to wear has resulted in loss of a great deal of fortune. This study was therefore an attempt to design and fabricate a wear testing machine, evaluate the performance of the machine and compare data obtained with existing ones. Materials for the various parts were carefully selected based on desirable properties and availability. Design calculations were made for the main shaft, compression spring, belt, pulley and electric motor. The post fabrication test was carried out on the machine to evaluate the performance of the machine and results gotten reported

    INCESSANT POWER SUPPLY IN NIGERIA AND THE NEED FOR THE DESIGN AND PRODUCTION OF 100,000MW POWER PLANT

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    This work entails study the causes, nature and effects of faults on the distribution network; evaluate the occurrence of faults and outages on feeders and distribution networks, and determine the reliability of the network.The present unreliable and erratic power supply is a pointer to the fact that there is a great need for fault evaluation and reliability studies of electric power system in Nigeria. The recent blackout in the country has grounded many activities and has destroyed many industrial processes. Also, the power industries face a lot of problems. Some of the highest priority issues being generation of sufficient power, urgent clearance of faults, adequate protection and increase reliability of the system, that is, bringing a steady uninterrupted power supply to the consumers. The Nigerian power problem resulted to incessant planned, forced and unplanned outages. In addition, it has resulted to erratic and unreliable supply of electricity in the country. It has reduced productivity and has increased unemployment rate in the country to over 40million (this figure is over 70% of Nigerian youths. It has led many of the youths in the country to crime. It has led many of the deaths of many innocent people in the country. Hence, an analytical method is developed to assess the dynamic- reliability of the distribution system, as well as optimizes the occurrence of faults along each of the individual consumer point in a feeder in order to improve the performance of the system. This research publication therefore evaluates the occurrence of faults which is about 856 occurrences during a period of 8 years and outages which range between 1118 to 3785 hours per annum along the distribution lines, also the failure rates of each of the feeders were analyzed in order to improve on the supply of electricity in the distribution network. The reliability of the system which ranges between 8.57*10-12 to 9.548*10-5 were analyzed; and fault clearing techniques were carried out. Efforts were made to adequately assess the failure rates of the feeders which range between 0.003 and 0.001 and reliability of the distribution system. Efforts were also made to improve the performance of the system. As a result, it was possible to establish improvement techniques which ensure adequate and constant supply of electricity to all the consumers for industrial growth and employment: a basic solution to increasing crime rate in the country

    RELIABILITY OF DISTRIBUTION NETWORKS IN NIGERIA

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    The incessant electric power supply problems facing the existence of industries in Nigeria is a pointer to the fact that there is great need for fault evaluation and reliability assessment of electric power system in the country and provide solutions. As it has been earlier said, this problem has grounded many activities and has destroyed many industrial processes. In view of this, a traditional analytical method is developed to access the occurrence of faults and outages along each of the individual consumer point in a feeder, as well as optimizes the reliability of the generation, transmission and distribution system. In view of this, it will be possible to improve on the performance of the system. It will also assist in the generation and transmission of sufficient power, clearing of faults, ensuring adequate protection and reliability of the distribution system that is, bringing a steady uninterrupted power supply to consumers within the distribution area and the entire country.Nigerians are experiencing a lot of difficulties as a result of poor Generation, Transmission and Distribution of electricity. As of 2016, the electricity energy consumption in the world from the world fact book revealed that the average power per capital (watts per person) in the United States is 1,377 Watts. In Canada, it is as high as 1,704 Watts per person and in South Africa; it is 445 Watts per person. The average power per capital in Australia is 1,112 Watts and in New Zealand it is 1,020 W per person. Whereas, the average electricity consumed in watts per person in Nigeria is just 14 Watts. This has put Nigeria in a rank of 189 out of 219 countries estimated. Currently, power generating capacity in Nigeria is estimated to be 6,803 megawatts, with average working capacity between 3,500 MW for over 170 million people (20.59 W/person). The power Companies in Nigeria face a lot of problems. Some of the highest priority issues being low generation of power, inadequate equipment and technical team for the clearance of faults, inadequate protection devices, transmission losses and low reliability of the distribution system. The Nigerian power problem has resulted to incessant planned, forced and unplanned outages. This has grounded many activities and has destroyed many industrial operations and processes. In addition, it has resulted to erratic and unreliable supply of electricity. It has reduced productivity and has increased unemployment and crime rates in the country. Hence, an analytical method is developed to study the dynamic- reliability of the distribution system, as well as optimizes the occurrence of faults and outages along the consumer point in each feeder in order to improve the performance of the system. A great need for fault evaluation and reliability studies of electric power system was observed. This research work analyzed the problems facing the Distribution System. Efforts were made to provide adequate solutions to the problems. The research work evaluated the occurrence and causes of faults and outages in the Distribution Network Area for a period of 8 years. In addition, it analyzed and reduced the effects of power losses along each of the feeders in the Distribution Network Area. This research work revealed the downtime, failure rate and reliability index along each of the eight feeders. It also improved the reliability and performance of the distribution system.Elizade University, Ilara- Mokin, Ondo Stat

    INCESSANT POWER SUPPLY IN NIGERIA AND THE NEED FOR THE DESIGN AND PRODUCTION OF 100,000MW POWER PLANT

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    The present unreliable and erratic power supply is a pointer to the fact that there is a great need for fault evaluation and reliability studies of electric power system in Nigeria. The recent blackout in the country has grounded many activities and has destroyed many industrial processes. Also, the power industries face a lot of problems. Some of the highest priority issues being generation of sufficient power, urgent clearance of faults, adequate protection and increase reliability of the system, that is, bringing a steady uninterrupted power supply to the consumers. The Nigerian power problem resulted to incessant planned, forced and unplanned outages. In addition, it has resulted to erratic and unreliable supply of electricity in the country. It has reduced productivity and has increased unemployment rate in the country to over 40million (this figure is over 70% of Nigerian youths. It has led many of the youths in the country to crime. It has led many of the deaths of many innocent people in the country. Hence, an analytical method is developed to assess the dynamic- reliability of the distribution system, as well as optimizes the occurrence of faults along each of the individual consumer point in a feeder in order to improve the performance of the system. This research publication therefore evaluates the occurrence of faults which is about 856 occurrences during a period of 8 years and outages which range between 1118 to 3785 hours per annum along the distribution lines, also the failure rates of each of the feeders were analyzed in order to improve on the supply of electricity in the distribution network. The reliability of the system which ranges between 8.57*10-12 to 9.548*10-5 were analyzed; and fault clearing techniques were carried out. Efforts were made to adequately assess the failure rates of the feeders which range between 0.003 and 0.001 and reliability of the distribution system. Efforts were also made to improve the performance of the system. As a result, it was possible to establish improvement techniques which ensure adequate and constant supply of electricity to all the consumers for industrial growth and employment: a basic solution to increasing crime rate in the country

    Survey of the Problems of Girl Child in Ekiti State, Nigeria

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    Objectives: To determine the prevalence of teenage pregnancy and knowledge of reproductive health problems among adolescent girls in Ekiti State, Southwest Nigeria.Methods: A cross-sectional community based study was conducted. Using convenient random sampling technique, four local government areas were selected. Eligible participants were both in and out of school children between the ages of 13 -18 years. A hundred respondents were sampled from each selected local government, making a total sample size of 400. Consenting participants were administered questionnaire in their homes by trained LGA enumerators. It elicited information on socio-demographic and reproductive health issues. Data collected were subsequently collated and analyzed.Results: Majority of the girls (78%) were still in-school. All were already menstruating, mostly attaining menarche between the age 15-16years. Only 212 (53%) could remember their last menstrual period. Sexual derby mainly occurred around age 15-16years; 53.3% were already sexually exposed. A quarter of respondents had been pregnant before. Only 187 (46.8%) were aware of modern contraception. The girls had a fair knowledge of implication of early sexual derby and unprotected intercourse, though it did not translate to behavioural change.Conclusion: There is a high prevalence of teenage pregnancy and poor reproductive health knowledge among teenagers in Ekiti State. More collective efforts involving parents, community heads, opinion leaders, civil societies and the state are needed to help our girls attain and sustain healthy reproductive behaviours

    Awareness and practice of emergency contraception at a private university in Nigeria.

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    BACKGROUND: The pursuit of formal education now causes many people in developing countries to marry later in life, thereby leading to increased premarital sex and unintended pregnancies. Efforts have been made to characterize awareness and use of emergency contraception (EC) among undergraduate students in public universities in Nigeria; however, it is not known if students in private tertiary institutions adopt different practices or if having an affluent family background plays a role. This pilot study therefore aimed to assess the awareness and use of EC among students at a private Nigerian university toward assisting education planners in developing strategies in improving students' reproductive well-being. RESULTS: Out of 94 female students, 42 (44.7%) had sexual experience, but only 32 (34.0%) were currently sexually active. Six students (6.4%) had had unwanted pregnancies, of which all but one were terminated. Fifty-seven respondents (60.6%) were aware of EC, though only 10 (10.6%) ever practiced it. The greatest source of EC information was from health workers and peers; the lowest source was family or relatives. Most respondents desired orientation and availability of EC on campus. EC awareness among the students was predicted by upper social class background (adjusted odds ratio [OR], 2.73; 95% confidence interval [CI], 1.06-7.45) and upbringing in the Federal Capital Territory (adjusted OR, 4.45; 95% CI, 1.56-14.22). CONCLUSIONS: Though awareness of EC was higher among the private university students in this study than at most public universities, there was no difference in EC usage. A high pregnancy termination rate was observed; dilatation and curettage were mainly adopted. In Nigeria, youth-friendly reproductive health information and access should not be limited to government-owned tertiary institutions but also extended to private ones

    Reshaping maternal services in Nigeria: any need for spiritual care?

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    BACKGROUND:High maternal and perinatal mortalities occur from deliveries conducted in prayer houses in Nigeria. Although some regulatory efforts have been deployed to tackle this problem, less attention has been placed on the possible motivation for seeking prayer house intervention which could be hinged on the spiritual belief of patients about pregnancy and childbirth. This study therefore seeks to determine the perception of booked antenatal patients on spiritual care during pregnancy and their desire for such within hospital setting.METHOD:A total of 397 antenatal attendees from two tertiary health institutions in southwest Nigeria were sampled. A pretested questionnaire was used to obtain information on socio-demographic features of respondents, perception of spiritual care during pregnancy and childbirth; and how they desire that their spiritual needs are addressed. Responses were subsequently collated and analyzed.RESULTS:Most of the women, 301 (75.8%), believe there is a need for spiritual help during pregnancy and childbirth. About half (48.5%) were currently seeking for help in prayer/mission houses while another 8.6% still intended to. Overwhelmingly, 281 (70.8%) felt it was needful for health professionals to consider their spiritual needs. Most respondents, 257 (64.7%), desired that their clergy is allowed to pray with them while in labour and sees such collaboration as incentive that will improve hospital patronage. There was association between high family income and desire for collaboration of healthcare providers with one's clergy (OR 1.82; CI 1.03-3.21; p?=?0.04).CONCLUSION:Our women desire spiritual care during pregnancy and childbirth. Its incorporation into maternal health services will improve hospital delivery rates
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