ASSESSMENT OF THE GEOTECHNICAL PROPERTIES OF TERMITE REWORKED SOILS

The determination of the geotechnical properties of inhabited termitaria (termite mounds) from three different locations in Lagos, Nigeria was carried out. Soil samples were taken at the cores of termitaria and also at 3m of either side of termitaria. Nine bulk representative soil samples depicting three termitaria soils and six adjacent soil samples were collected. Some geotechnical properties such as specific gravity, grain size distribution, consistency limits, linear shrinkage, CBR, and consolidation of the soils were determined. The chemical properties of the termitaria soil as compared to the adjacent surrounding soil was also analysed. The result showed that the geotechnical properties of termitaria are far better than the adjacent or surrounding soils. The activity of termites was identified as the primary cause of these improvements

Vibration-Based Structural Health Monitoring: Theoretical Foundations and Experimental Validation on Reinforced Concrete Beams

Quick identification of damages in structures is of great importance to engineers. Among the various techniques available for the evaluation of reinforced concrete structural integrity, non-destructive tests method remain a viable one as its use can lead to speedy decisions that bring savings on repairs or replacement of damaged reinforced concrete structures. This research uses modal parameter-based non- destructive tests to assess damages in reinforced concrete beams under static load. Four-point static loadings were applied to the 3 RC beams to induce three damage scenarios. After each static loading, a dynamic test was performed to access the degree of stiffness degradation. Modal frequencies and mode shapes obtained depicts clearly the stiffness degradations of the beams as the severity of damages on the beams became more pronounced. Results obtained showed that the research procedure adopted is a smart approach for damage assessment in reinforced concrete element

Nigerian Failed Developmental Strides: Can Agriculture Break the Jinx?

All over the world, industrialization is the principal underpinning of sustainable economic growth. But the attainment of industrialization and the accompanying economic stability that guarantee wellbeing for the population have not been that easy for the developing nations. In the free-for all quest for economic advancement, each people, nation, and continent adopt strategies it deems appropriate to pursue its goal. Agriculture have been a common denominator for all nations of the earth, whether developed or under developed. That has been the starting point for the advanced nations through the primitive age to the industrial revolution age to the present information/knowledge worker’s age. As they transited from one age to the other, they made use of acquired knowledge and available resources to move forward. Africa also started with agriculture through the primitive age to the current information/knowledge worker’s age without much to show in terms of economic stability and wellbeing of it citizens. This can be traced to the various approaches they adopted towards industrialization. Before independence, most African countries experienced sustainable growth with agriculture as the core activity. After independence, the discovery and exploitation of various types of mineral resources made many African nations to loose focus in agriculture thereby turning them to major importers of food. Over the recent years, Nigeria being one of such nations is faced with the burden of increasing food importation bill which in the near future may become unsustainable, there by creating crises that will destabilize the nation

IMPACT OF ECONOMIC CRISIS ON EDUCATION: CASE STUDY OF SOUTHWEST NIGERIA

The national politics determines the quality of education policies, programs and processes and eventually the products (results or outcomes). Government underfunding and commoditisation of education is likely to worsen the crisis in education. The current economic crisis confronting many governments is creating severe conflicts in educational sector of many nations. On the one hand they had to reduce, their budget deficits to avoid excess indebtedness. On the other hand, they had to promote education firstly to alleviate unemployment as a short run crisis measure and secondly to avoid the deterioration of human capital in the long run. High percentage of national budgets focuses on the public funding, which greatly affect the education sector. Some governments carried out overall budget cuts. These had negative effects on teachers, students and families. This research studies the impact of economic crises on education in the South-West part of Nigeria. The collected survey data shows that the current economic crisis in Nigeria had an observable impact on the education sector as many State Governments proceeded to drastic budget cuts on education. Only few State Governments, however, acknowledged the importance of the educational sector in overcoming the current economic crisis. These few States see the need of increased spending on education, supporting students, families and education providers as a way to enhance productivity and efficiency of State economy. The result of this research shows a great difference between the States cutting budget on education because of economy, economic downturn and those pumping more fund into education sector in the mist of economic crises. This research concludes that adequately funded educational system, if genuinely promoted and honestly managed is capable of creating mass-fully developed human talents whose creative thinking would get any nation out of the economic crisis and permanently shut the door to its future occurrenc

Assessment of Strength Characteristics of Concrete Made from Locally Sourced Gravel Aggregate from South-South Nigeria

Aims: The aim of this research is to verify the suitability of local gravel aggregates obtained from the Southern part of Akwa Ibom State for designed concrete production in place of crushed granite aggregate sourced from distance places at exorbitant cost. This paper assesses the strength characteristics of concrete made from two locally sourced gravel aggregates of 10 mm and 20 mm maximum sizes. Study Design: Three samples of gravels divided into washed and unwashed gravels were used for the research. Concrete mix design of 25 N/mm2 at 28 days of curing was the target mean strength of the research. Place and Duration of Study: Department of Civil Engineering, Covenant University, Ota – Nigeria, between September 2014 and July 2015. Methodology: Particle size distribution test, specific gravity test, water absorption test, aggregate crushing value test, flakiness and elongation tests, slump test, compressive strength test were performed on the samples. Concrete cubes150 mm were cast for each gravel size and three specimen tested for 3, 7, 14, 21 and 28 days compressive strength. Results: The washed gravels with 10 mm and 20 mm maximum size reached the target mean strength with 29.7 N/mm2 and 26.2 N/mm2 respectively while the unwashed gravel with 20 mm maximum size yielded a compressive strength of 24.5 N/mm2 at 28 days. Conclusion: The results prove that the size, grading, internal bonding and deleterious material contribute immensely to the strength of concrete made from gravel aggregat

STRENGTH PROPERTIES OF SLURRY INFILTRATED FIBROUS CONCRETE (SIFCON) PRODUCED WITH DISCRETE BAMBOO AND STEEL FIBRES

This paper examined the comparison between the mechanical properties of slurry infiltrated fibrous concrete with short steel fiber and discrete bamboo. The differences in properties of the concrete with fiber, concrete without fiber and concrete with discrete bamboo was determined. Compressive and flexural strengths of concrete and slump were also determined. A total of six mix batches of concrete containing 0% (control), 1%, 2% and 3% of steel fiber and discrete bamboo was incorporated into concrete, while 0%, 0.5%, 0.75% and 1.0% of steel fibre and discrete bamboo by volume fraction of concrete were used for flexural strength test. The bamboo stripes were sun dried, cut in sizes ranging from 50- 63mm in length and 4.4mm thick for easy mix with concrete while the steel fiber was 25mm in length and 0.4mm thick. The concrete prism used was 300mm x 100 mm x 100mm for compressive strength test and beam 350mm x 100mm x 100mm for flexural strength test. A thickness of 10mm cement slurry was infiltrated into the beam prism while the remaining 90mm thickness was filled with concrete. Plain concrete without fiber or discrete bamboo served as control. The addition of steel fibre increased the strength of concrete

Assessment of Quality of Steel Reinforcing Bars Used in Lagos, Nigeria

The process of designing a building structure starts with the selection of materials based on their properties and the type of stresses to be supported. For the design of reinforced concrete structure, which is one of the most built structures around the world, the choice will fall on concrete and steel reinforcing bars. The quality of concrete and steel reinforcement bars chosen must have adequate strength to guarantee a ductile behavior expected of reinforced concrete structure, so that the structure will be safe and functional to fulfil the purpose for which it is built. But this is not often the case in Nigeria, where the collapse of reinforced concrete structures have been very frequent. Possible causes of the failures are many including the quality of steel and concrete adopted. This research studies the strength of steel reinforcing bars used in 10 Local Government Areas of Lagos State, Nigeria. Samples of 10mm, 12mm, 16mm, 20mm and 25mm diameter bars were collected from building sites and tested in the State Laboratory. Results obtained show that an average of 70% of the 1325 samples considered met the BS8110 code specifications

Structural, Economic and Environmental Study of Concrete and Timber as Structural Members for Residential Buildings in Nigeria

The construction Industry in Nigeria is relatively monotonous in terms of the building material used, as evidenced by the vast number of residential buildings in Nigeria made of heavy weight materials such as concrete blocks. Since concrete is in high demand in the society, the cost of getting concrete constituent materials is becoming high thereby leading to high cost of living. This is largely due to the fact that alternatives to concrete for residential buildings in Nigeria are not readily available or explored. It is therefore of necessity to motivate stakeholders to alternative building materials that will not only rival concrete in cost, but also serve as a viable competitor in terms of sustainability, maintenance, constructability and client satisfaction in all necessary ramifications. With this in mind, timber has been selected in this research as “the” alternative material to rival concrete in the Nigerian building sector. This research studies both concrete and timber materials under structural, economic environmental and energy perspectives as to help designers with a choice of considering one over the other. This will give the Nigerian client, architect, engineer and builder the justification to choose one material over the other in order to meet the needs of the society. Various Autodesk software are adopted for Modelling and Structural Design of a duplex building of concrete and then timber materials. Cost Analysis of the two models are compared. Environmental Impact Assessment is conducted on the two building models with Athena Impact Estimator software. Results obtained are very promising for timber materia

Structural Properties of Concrete Containing Ground Waste Clay Brick Powder as Partial Substitute for Cement

With the increasing concerns on the impact of cement production on the environment and the need to protect the environment, the use of mineral additives as cementitious material to partially substitute cement is being considered as an effective option. One of such material is fired clay brick which can be sourced as generated waste from clay brick industry. This has an added advantage of reducing industrial waste and preserving the natural resources. The experimental objective of this study is to examine the possibility of utilizing clay brick waste as partial replacement for Portland cement in concrete. The clay brick was finely ground into powder size, and after grinding, the morphological characterization of the powder materials was carried out using scanning electron microscopy (SEM). Moreover, the chemical composition of the brick material was determined using X-ray fluorescence (XRF). Laboratory tests were carried out to determine the workability, split tensile and compressive strength properties of the concrete with 0%, 10%, 20%, 30% and 40% partial replacement of cement with ground clay brick (CB). From the test results, the chemical composition of the brick powder meets the standard requirements for pozzolanic material, with the SEM revealing an amorphous solid mass. The workability of the concrete reduces with increase in brick powder content. A significant improvement of the split tensile and compressive strength of the concrete was achieved at 10% cement replacement, after which a decrease in strength with increasing ground clay brick content was recorded. The use of ground clay brick of not more than 15% was recommended for concrete productio