Abstract Groundwater contamination by chlorinated hydrocarbons (CHC) is a common phenomenon that poses health risks to both humans and animals. These halogenated hydrocarbons infiltrate into the soil matrices and form pools at the bottoms of the aquifers thus contaminating the groundwater sources. Thermally enhanced soil vapour extraction (TSVE) using steam–air injection has gained popularity as an alternative technique to remediate the saturated and vadose source zones contaminated with C...
Abstract: This study was undertaken in Kitui South in Kitui County in the south eastern parts of Kenya. The main objective of the study was to develop a spatial model that can be used for selection of suitable sites for sand dam in Kitui South. Data analysis was done using three approaches. The first approach involved the use of the Remote Sensing (RS) technique where data was preprocessed and analyzed using Erdas Imagine software and Geographical Information Systems (GIS) for spatial modell...
Abstract: In this article, we investigate the use of an environmental waste (coal fly ash) in the manufacture of an ammonium nitrate corrosion resistant brick. Ammonium nitrate (AN) fertilizer spillages and vapors continuously corrode the civil structures in a fertilizer manufacturing plant situated in Zimbabwe. This situation is a safety hazard to more than a hundred plant personnel and hence a priority area for research. Our experimental results show that addition of sodium silicate improv...
Abstract: This work presents machine learning methods, particularly artificial neural networks (ANN) and multivariate regression analysis (MVRA) to create a mathematical model that will be used to predict the blasting effects in a Debswana diamond mine. These effects include airblast, ground vibration and rock fragmentation. We compare results from ANN, MVRA and empirical formulas using coefficient of determinant (R2) and root mean square error (RMSE). The ANN model with one hidden layer, 14...
The strength performance of UHPFRC with micro and hooked-ends steel fibers was studied in this paper using Finite Element (FE) modelling and simulation. The specimens were modelled in geometry, material, constraints, load and boundary conditions using ABAQUS package and dynamic explicit analysis was used to to investigate the crack pattern, failure mode and stress-stain behaviour of the UHPFRC specimens when subjected to uniaxial compression and tension loading. Results from the FE simulation...
ABSTRACT The Conventional Levenspiel and Smith fixed point continuous monitoring method is used in the evaluation of the dispersion number and the dispersion coefficient, I? of river Ebm under study. Comparisons were made with Agunwamba’s method and both methods for different results. The leverspiel and Smith method gave higher values than those obtained with the Agunwamba's method except in me station. This is due to experimental errors. The Agunwamba's method though more tedious gave mor...
ABSTRACT The objective of this research is to investigate the effect of addition of carbide on sewage degradation. To provide answers to the above objective, some laboratory tests were conducted which include Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total coliform, pH and Suspended Solids (SS) tests. Six experimental set ups of 5liters of sewage were constructed in the laboratory under anaerobic condition. Each of the sewage contained 0g (which served as control), 1g, ...
This research work, which presents a simplified technique of modelling steel fibers, uses python algorithm that can be directly run in ABAQUS to automatically generate the location and orientation of steel fibers in a rectangular ultra-high performance concrete specimen, so that the effect of steel fibers on the properties of such a specimen can be directly investigated through numerical simulation. This method is fast, can be applied to structural members of bigger dimensions (like beams,...
To study the effects of different types of bacteria on concrete. Develop a bacteria1 concrete by introducing the different bacteria. To study the efficiency of bacteria when mixed with mineral admixtures. Good compressive strength by arriving at optimum proportions by tria1. To make a comparative study of bacteria1 concrete with norma1 concrete.
ABSTRACT The primary purpose of this study is to identify the causes of rutting in highway pavements in the form of channelization particularly on wheel tracks resulting from high traffic repetitions and environmental effects. The rutting reduces the required performance due to poor hot mix asphalt (HMA) components and construction to mention a few. The study focused on the impact of fine aggregate angularity (FAA) to increase Asphalt layer stability. AASHTO testing method (T 304) was appli...
ABSTRACT The rate at which roads fail in Nigeria should worry any responsible citizen. Considering the enormous resource expended to construct a kilometer of road, it is heartbreaking when the same road fail barely six (6) months after construction. For in the life of our dear country, the all-important economic theory of opportunity cost is applicable just as it is elsewhere in the world. Stabilization is a viable alternative to achieving a durable road construction regime. Soil stabilizati...
TABLE OF CONTENTS ABSTRACT . . ACKNOWLEDGEMENT LIST OF TABLES LIST OF FIGURES LIST OF SYMBOLS CHAPTER ONE: INTRODUCTION . * . . . . 1.1 Approach To Elasticity Problems-General .. 1.2 Reduction Of A Two-Dimensional Problem To A One-Dimensional One . . . . 1.3 Vlasov's Mixed Method , . . 1.4 Aim And Scope . @ . . 1.5 Review Of Literature .a . . CHAPTER TWO: FORMULATIONS OF THE GOVERNING EQUATIONS .. 0. . . 2.1 Plane Stress Formulation . . a . 2.2 Plane Strain Case . . . . . . ...
This work considers the shear behavior of reinforced concrete beams using granite as coarseaggregate without shear links. Four reinforced concrete beams were cast and tested to understandthe shear behavior with varying tension reinforcement ratios. The beams were cast in two pairs;the first pair had a depth of 184mm, a width of 110mm, and a length of 1500mm. The second pairhad a depth of 150mm, a width of 90mm, and a length of 1000mm. The first and second pair ofbeams had span-to-depth ratios...
ABSTRACT The need to clean-up heavy metals that contaminate water cannot be over emphasized. This paper examined the kinetics of lead adsorption using activated rice husk ash. The influences of contact time, adsorbent dose, pH and temperature on adsorption were investigated. From the results obtained, by analyzing the effect of contact time, it was discovered that maximum adsorption of about 90 % removal efficiency took 240 minutes using 0.2g of adsorbent. While in testing for the effect of...
ABSTRACT Thin-walled box girder bridges are very efficient structural solution for long-span bridges because of their high torsional resistance, stability, economy, and aesthetic appearance. Though, this type of bridge is not common in Nigeria, it is envisaged that they may offer economic advantages in future high way projects in Nigeria. Analytically, however, the box girder bridge is a very complex indeterminate problem. Therefore, the primary objective of this research was to produce a r...