Evaluation of the Structural Performance of Lateritic Soil Stabilized with Cassava Peel Ash (CPA) and Cement

This study presents the result of experimental investigation on the evaluation of the effects of Cassava Peel Ash (CPA) on the index and structural properties of lateritic soil of A-7-5 (AASHTO Classification) and SP soil (USCS classification) respectively. The study was in two phases, firstly with the addition of CPA only by weight of dry soil and secondly with the addition of 5% cement with the CPA by weight of dry soil. The CPA additions were performed using 0, 2, 4, 6, 8 and 10% increment by weight of dry soil thoroughly mixed. The results of the treated soil showed that the index properties: plastic limit and the maximum dry density (MDD) decreased as the CPA addition increased whereas the liquid limit, plasticity index, Optimum Moisture Content (OMC) and California Bearing Ratio (CBR) increased as the CPA content increased. It was also discovered that the Unconfined Compressive Strength (UCS) increased up to 4% of CPA addition after which was a reduction. This implies that CPA possesses the potential for use in the modification/ stabilization of lateritic soils. Thus the use of CPA in road construction works can be said to have two major advantages – as an effective agricultural waste management and the improvement of road construction soils for better road performance

Assessment of the Strength of Conventionally Produced Sandcrete Blocks and Burnt Bricks

The fact remains that housing has been universally acknowledged as the second most important human need after food. It has been of perennial interest to the world at large since its availability touches on one of the widest spectrum of human existence. Sandcrete blocks as building materials have become so popular in many parts of Africa that although similar to bricks in many respects, they both deserve to be treated separately. It is therefore worthy of note that for an engineer to select one of these materials (block and brick), the fitness or suitability of the chosen materials for the purposed structure must be considered.Tests carried out in this research include sieve analysis, Atterberg’s limit tests (Liquid limit and plastic limit) were carried out on the materials (sand andlaterite)to be able to ascertain certain of their properties for their intended use. About ten pieces each of sandcrete block and burnt bricks were prepared for the study and density and compressive strength tests were carried out on them. Findings of the study shows the samples Liquid Limit to be 32%, Plastic Limit of 16.7%, density of the sandcrete block is 1947.47kg/m3 while the density of the burnt brick is 1823.58kg/m3 .The average compressive strength of burnt brick (5.20N/mm2 ) was found to be higher than that of sandcrete block (3.15N/mm2 ).This shows that the compressive strength is directly proportional to the crushing load on the specimens and this is shown by the regression equation y = 0.2129x+1.5;R² = 0.9817 for the burnt bricks and y = 0.14x + 0.7; R² = 0.9942 for the sandcrete blocks.The study therefore concludes that burnt bricks just like sandcrete blocks is a good construction material and can be used for sustainable building construction

PUBLIC TRANSPORT POLICY IN DEVELOPING COUNTRIES: NIGERIA AS A CASE STUDY

This paper reviewed understudies public transport approach utilizing factors such urbanization, populace development, vehicle proprietorship, and utilization. With changes in the social, political and economic climate of Nigeria, this study looks at how these changes have affected transportation request and supply, transport arrangement and directions, and parts of economic aspects and fund identified with public transport. Conservation and enhancing of existing modes, effective utilization of people in general transport administration framework, executing appropriate transportation measures, and empowering a move towards reasonable modes were suggested. Review of government policies towards public transportation was undertaken and it shows that if developing nations like Nigeria are to achieve their economic transformation blueprint such as the Millennium Development Goals (MDGs), they require a functional, reliable and effective transport system to, among other things, connect people, places, services, opportunities and all these can only be derived by properly formulated and implemented policies with the aid of all relevant private, academic and government bodies working together

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

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

Structural Evaluation of the Effect of Pulverized Palm Kernel Shell (PPKS) on Cement-Modified Lateritic Soil Sample

There have been global efforts to reduce environmental pollution of agricultural and industrial waste products by utilizing such wastes as stabilizing agents to improve soils for various uses, especially road construction. In this research, lateritic soil sample obtained from a borrow pit was tested with varying percentages of Pulverized Palm Kernel Shell (PPKS). The soil was classified as A-6 (AASHTO classification) using standard soil laboratory tests. Laboratory tests such as Atterberg Limits, Compaction, Unconfined Compressive Strength (UCS) and California Bearing Ratio (CBR) were conducted on the soil + PPKS mix only and also on soil + PPKS + 3% Ordinary Portland Cement (OPC) mix. The liquid limit (LL) and plasticity index (PI) values decreased steadily with increase in PPKS while the plastic limit (PL) value increased with up to 4% PPKS addition after which the values started decreasing. The shrinkage limit (SL) value increased with a peak value at 8% PPKS addition after which the values began to decrease. The Optimum Moisture Content (OMC) results on PPKS addition increased from 16% to 19.5% while the Maximum Dry Density (MDD) decreased by 45.18% from 1.669g/m3 to 0.915g/m3 . Addition of PPKS decreased the Unsoaked CBR by 10.79% from 68.60 to 61.20% while the Soaked CBR increased by 74.12% from 18.05% to 69.75%. UCS values for the lateritic soil and PPKS for the uncured sample, at 7 days and 14 days had peak values of 85.03, 96.46 and 100.44 respectively. From the study, it can be concluded that the properties of the Lateritic soil improved when stabilized with Cement and pulverized palm kernel shell compared to when it was stabilized with pulverized palm kernel shell alon

Performance Study of University of Ado Ekiti (UNAD) Transit Shuttle Buses

Traffic engineering uses engineering methods and techniques to achieve the safe and time efficient movement of people and goods on roadways. The safe and time efficient movement of people and goods is dependent on the transit system performance, which is directly connected to the traffic characteristics. The main parameters of performance of transport shuttles are traffic volume, speed, density and revenue; and all these are evaluated in this study. In the absence of effective planning and traffic management, current road infrastructure will not be able to cater for the future needs of the University. Students, staff and vehicle volumes have increased significantly in the last decade in the Institution, yet the performance of the transport shuttle have been dismal and unable to achieve its objectives. Findings of the study show that the morning peak period (8.00am to 9.00am) has 234 vehicles/hr, evening peak period (2.00pm to 3.00pm) has 284 vehicles/hr, while the offpeak period (11.00am to 12.00pm) has 156 vehicles/hr. The journey time from the Post Office bus stop to the University campus, measured as 34.01 minutes, was too long for the distance of 15.0km road which according to the Nigeria Highway Code should not be more than 18 minutes. The average stopping time was 6.55 minutes, average interval between arrivals of motorists was 16.40 seconds, the average queue length was 14.23 people, and the average waiting time at the bus-stop 4.17 minutes. These values were obtained using the queuing theory and shows much commuters time is lost on transit queues. The financial condition of the transit unit shows that amount generated is less than the amount expended by the transit operators. This means, in effect, that the shuttle bus operators are operating in deficit

Microstructural Analysis of Concrete Using Cow Bone Ash for Alkali-Silica Reaction (ASR) Suppression

Concrete pavements are prone to microstructural changes and deterioration when exposed to Alkali-Silica Reaction (ASR). ASR results in strength reduction, cracking, spalling and other defects in the concrete if left unchecked. Supplementary Cementitious Materials (SCMs) such as Cow Bone Ash (CBA) however can be used to improve concrete performance, hence its use in this study. Concrete samples were prepared at replacement levels of 0%, 5%, 10%, 15%, 20% and 30% of cement with Cow Bone Ash. The concrete samples were then subjected to petrographic and Scanning Electron Microscopy (SEM) analysis. Petrographic examination shows that the minimal and least amount of ASR gels and micro cracking were observed at 15% CBA replacement of cement in the concrete samples. Scanning Electron Microscopy (SEM) analysis shows that changes in the elemental composition of the concrete samples is related to the effect of CBA which enhances adhesion in the concrete. SEM analysis show that, in general, the change in microstructure in the concrete was mainly due to the change in the arrangement of the C-H-S compounds. The microstructure analysis indicates that CBA in concrete influences the densification of the concrete at the transition zone, resulting in a much lower porosity. This results in the concrete having a tightly bound layer that repels ingress of water and thereby inhibiting cracks and gel formation as water is a contributing factor to the ASR in concrete

Design and Development of a Wear Testing Machine for Manufacturing Laboratories

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

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

The Effect of Curing Media on Compressive Strength of Microbial Laterite Concrete

Concrete is widely used in the construction of infrastructures and also, its compressive strength determines the function under the application of load. This research investigated the effect of curing media on compressive strength of microbial laterized concrete. 216 numbers of microbial laterized concrete cubes (150x150x150mm) batched by volume at 1:2:4 and water cement ratio of 0.5 were produced from Portland lime cement, aggregates (fine and coarse), laterite and bacteria (bacillus sp. Ct-5) water. Laterite was added at 0%, 15% and 30% respectively. They were then cured in four curing media; Distilled Water, Bacteria + Nutrient Broth Water, Bacteria Water, and Nutrient Broth Water for 28days. Compressive strength test was carried out at 7, 14, and 28 days respectively and some of the results were recorded as 17.38 kN/m2, 22.00 kN/m2, 22.24 kN/m2 etc. The result shows that the compressive strength 22.24 kN/m2 of concrete produced with zero percent laterite, mixed with bacillus sp. CT-5 water, and cured in nutrient broth + bacteria water was found to be most significant when compared with control and other media test results. It can be concluded that bacillus sp. Ct-5 can be easily cultured and safely used in improving the compressive strength of microbial laterized concrete