Showing papers in "Civil and environmental research in 2012"

Oil Exploration and Spillage in the Niger Delta of Nigeria

Abstract: Colonel Drake drilled a 70 feet well in Titusville, Pennsylvania and discovered oil. In 1956, Shell British Petroleum discovered crude oil in the Niger Delta within Nigeria and since then oil exploration and exploitation have been ongoing for several decades. The Niger Delta consists of highly diverse ecosystems supportive of numerous species of terrestrial and aquatic fauna and flora and is the largest wetland in Africa. The oil spillages ongoing for several decades have characterized the area by contaminated rivers, stream and forest, which constitutes the major income source for the majority of the local population inhabiting the region, which are mainly dependent on ecosystem services. Approximately 1.5 million tons of oil has been spilled within the Niger Delta region over the span of several decades, most of which was partially cleaned or not cleaned totally, making some areas wastelands. Statistical analysis carried out for oil spillage quantities and incidence between 1976-2000, showed decrease in oil spillage quantity and increase in oil spillage incidence. These results were based on figures the oil companies submit to the government and one would not expect them to represent the actual figures. Reliable data could not be obtained for the most recent spills, more extensive evaluation is required. Keywords: Oil, Spillage, Niger Delta, Nigeria

Removal of Oil from Oil Produced Water Using Eggshell

Abstract: The presence of dissolved crude oil in water poses significant environmental hazards to aquatic lives. Components of dissolved oil, BTEX which are carcinogenic can cause cancer after a long time of exposure. Eggshell, a potential biosorbent was used to remove both dissolved and dispersed oil in produced water. It was conditioned to provide good oil uptake in its natural form. The biosorbent material was characterized using FT-IR, SEM, XRD, BET and EDS techniques. The results showed that eggshell contains calcium, carbon and oxygen in proportions of 37.4, 48.5 and 14.1 atomic percent respectively. Biosorption experiments with the eggshell biosorbent showed that it can be used for crude oil removal from produced water providing almost 100% at concentration of 1.8 g eggshell/L of produced water and oil concentration as high as 194 mg/l. Several kinetic models were tested and it was discovered that the biosorbent followed pseudo-second order biosorption kinetics. The value of q e deduced from the slope of the curve was 108.69 mg/g and the value of rate constant (k 2 ) was found to be 0.019 g.mg -1 min -1 . This result showed that eggshell is a good biosorbent for crude oil removal in produced water. It will provide a cheap way of cleaning oily contaminated water environment thus safeguarding human health, aquatic lives, and soil fertility. Keywords: eggshell, oil removal, produced water, environment, biosorption, biosorbent

A Review on Effects of Stabilizing Agents for Stabilization of Weak Soil

Abstract: Soil stabilization is a process to treat a soil to maintain, alter or improve the performance of the soil as a construction material and very important to minimize the cost of earth work in case of unavailability of good earth at nearby source. The use of Stabilizing agent, for sub-grade with weak soil, improves strength parameter such as cohesion and improvement in cohesion leads to strengthening of embankment. This will ultimately lower down the road construction cost. This paper specifically addresses about soil stabilizing agent which are used to stabilize weaker soil to improve subgrade quality. In this paper review on use of different stabilizing agents such as lime, fly ash, cement, rice husk, geo-grid, chemical stabilizing agents etc.is done to analyze effect of stabilizing agent for application for stabilization of soil of Gujarat region.

Exploring the Challenges and Barriers in Accessing Financial Facilities by Small and Medium Construction Firms in Ghana

Abstract: This study sought to explore the challenges and barriers facing Small and Medium Construction Firms (SMCFs) in Ghana in their quest to access finance from financial institutions for their business purposes. This study was a cross-sectional survey that used semi-structured questionnaire to collect data from the sample. 50 questionnaires were distributed to construction firms in Kumasi and Accra Metropolis through a convenience sampling technique. The findings are that the key challenges that make it difficult for SMCFs to access finance include policy regulation, inadequate financial infrastructure, stringent collateral security requirement, and lack of institutional capacity of SMCF sector. The key barriers identified include informational barriers, lack of managerial skills with SMCFs. Limitations of the study have been noted and recommendations for developing innovative approaches to making finance accessible to SMCFs in Ghana have been discussed. The study contributes to the body of knowledge in the area of financing construction firms in developing countries in general, and in Ghana in particular. Keywords: Access, Challenges, Finance, Construction firms, Ghana.

Evaluation of the Factors Influencing Time and Cost Overruns in Telecom Tower Construction in Ghana

Abstract: This paper, sought to empirically evaluate the factors influencing time and cost overruns of the telecom tower construction projects in Ghana. It involved a cross-sectional survey that used a self-administered structured questionnaire administered to sixty seven respondents of telecom tower construction professionals. The study found 15 major factors influencing time overruns and 14 major factors causing cost overruns in telecom tower construction projects. It also revealed that telecom tower construction projects executed between 1992 and 2011 experienced as much as 82% time overruns, and the cost of the projects increased by 50%. The paper contributes to the general body of knowledge in the area of project management particularly in Ghana’s construction industry. Recommendations are also made for clients, contractors and consultants to alleviate delays in the construction of telecom tower construction projects. Keywords: cost overruns, evaluation, telecom tower construction, time overruns

Delay, fuel loss and noise pollution during idling of vehicles at signalized intersection in Agartala city, India

Abstract: Agartala, capital of Tripura, India faces traffic congestion particularly in the different road intersection due to rapid and uncontrolled development by an unacceptable level of disparity in transportation demand and supply scenario resulting in environmental degradation as well as delay and fuel loss. When the vehicles are waiting for their turn to clear the intersection, the drivers normally keep the engines of their vehicle on and unnecessary hoot horns. As a result vehicle delay, fuel loss & noise level are increased particularly at the signalized intersection. 5 (five) representative signalized intersections of varying traffic volume have been selected in this study to ascertain delay, fuel loss & noise level during idling of vehicles. The study indicates that the noise level exceeds permissible levels and vehicular delays are high as more than 60 sec/vehicle during peak hour at all important signalized intersections. The study reveals that North Gate intersection is found to be the busiest intersection as well as the noisiest intersection. In North Gate, during daytime noise level is in between 66.7 dB (A) to 108.6 dB (A) and during night time 60.4 dB (A) to 100.9 dB (A) which is ill effective on human health and environment. In Math Chowmuhani intersection fuel loss is maximum comparing to other four intersections. A direct correlation between vehicular delay versus noise level, traffic volume versus delay and traffic volume versus noise level have been proposed. These equations could be used as an effective tool in traffic management, land use planning and pollution control. After implementation of remedial measures, vehicular delay, fuel loss and noise level of all signalized intersection of Agartala city can be reduced. Delay, fuel loss and noise level at different signalized intersection of Agartala city and strategies to control the noise pollution have been discussed in this paper. Keywords: Signalized Intersection, Average Daily Traffic (ADT), Noise Level, Fuel loss

Generation of Groundwater Quality Index Map: A Case Study

Abstract: Reliance on groundwater has been rapidly increasing, especially in the arid and semiarid regions, resulting in its overexploitation leading to deterioration of quality. Kurmapalli Vagu basin of Andhra Pradesh, a semi-critical region with respect to the stage of groundwater development is a good example. Its monitoring and assessment is imperative for devising preventive measures against health hazards. Groundwater samples from twenty five locations were collected and analyzed for various physico-chemical parameters in terms of Water Quality Index (WQI) to determine its suitability for drinking purposes. Seven locations were found to have WQI value within the limits. High values of WQI were mostly due to high content of Fluorides. WQI Contour map was generated to study spatial distribution of quality of groundwater. Suitable remedial measures and groundwater augmenting structures are proposed in the study area to improve the quality of groundwater. Keywords: Groundwater, WQI, Fluorosis, Groundwater augmenting structures.

Influence of Human Activities on the Water Quality of Ogun River in Nigeria

Abstract: The quality of Ogun River in south-west, Nigeria was investigated by a field survey; covering the dry season and rainy season. Water samples were collected from seven sites (including an Abattoir, a market, residential community and a brewery); analysis of the physico-chemical parameters using standard methods and their environmental effects on the river were investigated. Generally, the value/degree of dissolved oxygen, phosphate, BOD, COD, pH, temperature, hardness from the sites during the rainy and dry seasons were compared with the World Health Organization (WHO) standards for domestic and commercial water. The traces of some hazardous physical and chemical impurities in the river were above the acceptable limits; and thereby pose a health risk to several rural communities who rely heavily on the river primarily as their source of domestic water. The study revealed a need for continuous pollution monitoring and management program of surface water in Nigeria. Keywords: surface water, water quality, water pollution, field survey, physico-chemical analysis

Effect of Nitric Acid Concentration on the Compressive Strength of Laterized Concrete

Abstract: Laterized concrete is concrete in which some or all of the fine aggregates is from laterite. In this s tudy, the effects of varying nitric acid concentrations (0%, 5%, 10%, 15 %, and 20%), mix proportions (1:1:2, 1:1Ω:3), expos ure period (28, 56, and 84 days) and percentage laterite conte nt (0%, 25%, and 50%) on the compressive strength of laterized concrete were investigated. The tests were carried out with a view to simulating the performance of la terized concrete in contact with soluble nitrate-based subs tances. 100x100x100mm cubes of laterized concrete were cast and moist-cured for 28 days and the strength of concret e at this age was determined. The cubes were therea fter immersed in 0%, 5%, 10%, 15%, and 20% concentrations of nitric acid for a total of 84 days. Compressive strengt h tests were carried out at the end of 28 days, 56 days and 84 d ays of immersion. The results of the tests indicate d that the compressive strength significantly reduces with inc rease in acid concentration, immersion period and l aterite content. The effect of richness of mix on resistance of late rized concrete to the acidic aggression becomes mor e pronounced at the highest (50%) laterite content. Keyword: compressive strength, laterized concrete, nitric a cid concentrations, percentage laterite content.

Structural Strength Characteristics of Cement-Cassava Peel Ash Blended Concrete

Abstract: This study focuses on structural strength characteristics of cement-CPA blended concrete. Cement was replaced partially by CPA between 5 and 25% by weight of cement at 5% interval. Water binder ratios (w/b) of 0.5, 0.55, 0.6, 0.65 and 0.7 were used to produce the blended concrete of mix 1:2:4. The results of the investigation indicated that as the replacement of CPA increases, more water was required to make the blended concrete workable, hence, w/b of 0.7 was found to be optimum to produce workable blended concrete. The compressive strength of the blended concrete increases with age and reduces with increase in CPA content but at 5, 10 and 15% CPA the strength activity indices (SAIs) are 83, 82 and 79% at 28-day while at 120-day strength SAIs are 99, 95 and 87% showing that CPA contributes to later strength development than early strength development, a property that is peculiar to pozzolanic materials. Also, these values were greater than 75% specified by ASTM C311-98 showing that up to 15% is adequate. Similar trend was observed for flexural strength development as flexural crack was independent of the CPA content in the blended concrete. The results further show that CPA does not have appreciable influence on the density of the blended concrete. Regression analysis was conducted on the data and models showing relationship between compressive strength and curing ages for up to 15% CPA are proposed Keywords: Cassava peel ash, cement, pozzolan, workability, compressive strength and flexural strength

Biosorption of Heavy Metals from Aqueous Solutions Using Water Hyacinth as a Low Cost Biosorbent

Abstract: In this study, biosorption of Cu(II) and Zn(II) ions from aqueous solutions by water hyacinth fiber was investigated as a function of initial solution concentration, initial biomass concentration and temperature. Solutions containing copper and zinc ions were prepared synthetically in single component and the time required for attaining adsorption equilibrium was studied. The optimum sorption conditions were studied for each metal separately. The adsorption equilibrium data were adequately characterized by Langmuir, Freundlich, Temkin and Dubinin-Radushkevich equations. The equilibrium biosorption isotherms showed that water hyacinth possess high affinity and sorption capacity for Cu(II) and Zn(II) ions, with sorption capacities of 99.42 mg Cu 2+ and 83.01 mg Zn 2+ per 1 g biomass, respectively. All results showed that water hyacinth fiber is an alternative low cost biosorbent for removal of heavy metal ions from aqueous media. Keywords: biosorption, low cost biosorbent, wastewater treatment, heavy metal

Investigation of the Geotechnical Engineering Properties of Laterite as a Subgrade and Base Material for Road Constructions in Nigeria

Abstract: This project is an indepth investigation of the ge otechnical engineering properties of subgrade and base soils used in the construction of Omolayo Road in Akobo Area of Lagelu local government, Oyo State, Nigeria. Subgrade samples were collected at chainages 0+000, 1+000, 2+000, 3+000 and 4+000 respectively at depths ranging 0.5m to 1.0m, while the base sample was collected from one of the heaps of laterite brought from the borrowpit at Oluwo area along New Ife Express Road, Oyo State, Nigeria. The samples were subjected to the following laboratory tests; Particle (grain) size analysis, Atterberg limit test, Compaction test, California bearing ratio (CBR) test and Specific gravity test. The particle size analysis results showed that all samples, both subgrade and base were well graded since their Uniformity Coefficients were greater than 15. It further revealed that base sample were more plastic compared to subgrade samples since it has highest percentage of clay passing sieve no. 200 (75µm) i.e. 27.60%. This indicates that samples with high silt clay content are susceptible to volume changes when wet. The liquid limit and plastic index range from 24% to 48% and 2.7% to 25% respectively with base sample having the highest in both cases. This shows that base sample has high clay content and its load bearing capacity could be reduced when wet. The maximum dry densities ranged from 1.90mg/m 3 to 2.19mg/m 3 and Optimum moisture contents range from 5.4% to 14.2% respectively. The California bearing ratio is from 78% to 132% (unsoaked). The Specific gravity results ranged from 2.65 to 2.68. The samples were classified using AASHTO classification. The AASHTO system classified the subgrade samples as A�1�b and A�2�4 constituting 50% and 33.3% respectively, and base sample classified as A�2�7 c onstituting 16.6%. This shows the subgrade samples are excellent to

Influence of Compactive Efforts on Compacted Foundry Sand Treated With Cement Kiln Dust

Abstract: Laboratory tests were carried out on foundry sand treated with up to 12% cement kiln dust (CKD) by dry weight of soil to determine its suitability for use as road pavement material. Specimens were compacted at the energy levels of Standard Proctor (BSL), West African standard (WAS) and British standard heavy (BSH). The foundry sand utilized in this study is classified as A-2(0) or SM using the America Association of Highway and Transportation Officials (AASHTO) and the Unified Soil Classification System (USCS), respectively. The 7day unconfined compressive strength (UCS) values recorded for the natural soil at BSL, WAS and BSH compactive efforts record values of 165, 316 and 344 kN/m 2 respectively, while peak values of 416, 378 and 444 kN/m 2 were recorded at 8 % CKD, 6 % CKD and 6 % CKD treatments of foundry sand, respectively. None of the Specimens attained the UCS value of 1710 kN/m 2 conventionally used as criterion for adequate cement stabilization. California bearing ratio values recorded for the untreated foundry sand at BSL, WAS and BSH compactive efforts are 4, 6 and 8%, respectively. While peak California bearing ratio values of 15, 20 and 52% were recorded at 12% CKD treatments for BSL, WAS and BSH compactive effort respectively. The CBR values of 20 and 52% at treatment level of 8% CKD for WAS and BSH compactive effort satisfy the recommended minimum CBR value of 20-30% when compacted at optimum moisture content and 100% West African standards for sub-base material. The durability of specimens determined by immersion in water failed to produce an acceptable loss in strength value of less than 20% as specified for tropical soils. Keywords: Cement Kiln Dust, Compacted Durability, California bearing ratio, Unconfined Compressive strength,

Effect of Pollution on Comman Man in India: A Legal Perspective

Abstract: The present generation and the coming generations have to solve three grave problems, namely, population, poverty and pollution if they have to survive. We will focus ourselves on pollution for now. The environmental problems in India are growing rapidly. The increasing economic development and a rapidly growing population that has taken the country from 300 million people in 1947 to more than one billion people today is putting a strain on the environment, infrastructure, and the country’s natural resources. Industrial pollution, soil erosion, deforestation, rapid industrialization, urbanization, and land degradation are all worsening problems for our country. Overexploitation of the country's resources, be it land or water and the industrialization process has resulted environmental degradation of resources. Environmental pollution is one of the most serious problems that is facing humanity and other life forms on our planet today. It is no longer a new or surprising fact that mankind has actually brought the Earth to the brink of disaster. Man’s suicidal actions will soon turn this wonderful planet into a lifeless and hostile planet. The ill-effects of ever-growing population and urbanization have already been seen, felt and realized to some extent in different circles. Today, the air we breathe, the water we drink and the land on which we grow our food, have been poisoned. Numerous problems like ozone layer depletion, greenhouse effect, global climatic changes, depletion of ground water levels, drinking water crises, etc. are all plaguing the Earth today in the twenty-first century and posing serious threats to the survival as well as the very existence of the human race on this Earth. Industrialization and urbanisation have resulted in a profound deterioration of India’s living quality. Out of the 3 million premature deaths that occur in the world each year due to pollution, the highest number are assessed to occur in India. According to the World Health Organization, the country of India is one of the top ten polluted countries in the world. According to another study, while India’s Gross Domestic Product has increased 2.5 times over the past two decades, while the pollution has quadrupled in the same period. Through the paper we will be throwing light on various forms of pollution prevalent in India and their effect on the common man of the country. And the measures that can be used to curb the pollution and minimize the effect of pollution on the people. Mahatma Gandhi had said that nature has enough to satisfy everyone’s need but has not enough to satisfy man’s greed. Sadly our ever-expanding greed has put us in such precarious situation that we face today. Keywords: Pollution, Law, Environment, People, Legal Perspective

Communication of Construction Health and Safety Information in Design

Abstract: Although all parties involved in the construction industry may address their respective responsibilities, the lack of integration between each organization often results in communication problems which jeopardize health and safety (H&S). Of particular note is the communication during the design phase. All information pertaining to the project must be readily accessible for all parties, to ensure smooth and hitch-free project execution. This paper presents the challenges in the communication of H&S information in the design phase of construction projects derived from semi structured and focus group interviews with 53 construction practitioners in the UK. It characterizes the various aspects of collaborative communications at this stage and highlights the problem area. Keywords: Construction H&S, Communication in Construction, Communication of H&S, Design Phase and Construction Management

Cost Entropy and Expert System Approach to Modeling Cost Smoothing System in Reinforced Concrete Office Building Projects Procurement

Abstract: The main aim of this research work is to develop an expert system approach to cost smoothing model in reinforced concrete office building project procurement. An econometric model which incorporates exigency escalator and inflation buffer, with entropy threshold for a typical reinforced concrete office building, useful at tendering and construction stages of building projects was developed in this study. As built and bill of quantity value of twenty (20) building projects initiated and completed within 2008 and 2009 were used at random. Elemental dichotomies within the context of early and late constructible elements with speculated prediction period was used, taken into consideration the present value of cost. This attributes would enable a builder or contactor load cost implication of an unseen circumstance even on occasion of deferred cost reimbursement with the aid of average entropy index developed for each project elements. The model was further validated with new samples and discovered to be of high Eigen and contingency coefficient values. The model could help in cost smoothing at different stages of reinforced concrete office building which could further aid cost overrun prevention. Keywords: Expert system, Smoothing, Entropy, Dichotomy.

Formulation of Seismic Passive Resistance of Non-Vertical Retaining Wall Backfilled

Abstract: The seismic passive earth pressure is really the most important parameter in some special cases like key analysis, anchor analysis, foundation analysis etc The simultaneous action of weight, surcharge, cohesion and adhesion is also taken into consideration A visual presentation is made by plotting graphs with the wide range of variation Parameters like angle of internal friction, angle of wall friction, wall inclination angle, cohesion ( c ), adhesion ( c a ), seismic accelerations ( k h , k v ), surcharge loading ( q ), unit weight, height ( H ) to provide the variation of seismic passive earth pressure coefficient Keywords: Pseudo-static, seismic passive resistance, single wedge, rigid retaining wall, wall inclination

Rainfall-runoff modelling of a watershed

Abstract: In this study an adaptive neuro-fuzzy inference system was used for rainfall-runoff modelling for the Nagwan watershed in the Hazaribagh District of Jharkhand, India. Different combinations of rainfall and runoff were considered as the inputs to the model, and runoff of the current day was considered as the output. Input space partitioning for model structure identification was done by grid partitioning. A hybrid learning algorithm consisting of back-propagation and least-squares estimation was used to train the model for runoff estimation. The optimal learning parameters were determined by trial and error using gaussian membership functions. Root mean square error and correlation coefficient were used for selecting the best performing model. Model with one input and 91 gauss membership function outperformed and used for runoff prediction. Keywords : Rainfall, runoff, modelling, ANFIS

Mass Housing in Nigeria, Customize the Brief: Provide a Desired House

Abstract: The nature of the housing designs in mass housing schemes in Nigeria is a function of how architects were trained to handle mass housing designs It is common practice to find that the houses in majority of the mass housing schemes in Nigeria are never owner specific It is often assumed by architects working on mass housing schemes that the process of making the houses specific is cumbersome The nature of the construction method of these mass housing schemes allows for the design briefs of the individual house to be different This paper examines how design brief in mass housing in Nigeria can be customized This is done through the development of a customization brief model with aid of a network of computers It is expected that if the model is applied into mass housing in Nigeria, desired house by house owners in mass housing schemes would be met Keywords: architects, customization, house owner, mass housing, model

Research on the Concrete Dam Damage and Failure Rule under the Action of Fluid-Solid Coupling

Abstract: This paper evaluates the stability of concrete dam under the action of fluid-solid coupling in the two working conditions of water level raising and rainfall intensity increasing with the method of strength reduction, and the conclusions are revealed as follows: The unstable failure of dam always starts from the slope base, the crack on the slope top and the creep slip in the slop base developed, which led to the gradual destruction of the dam and formed the slip surfaces through the dam; the safety factor of the concrete dam reduced and the potential slip surfaces moved to the inside of the dam with the water level raising; the more rainfall intensity, the larger plastic yield region and the lower safety factor will be, and the dam slip surfaces transferred from the base of slope to the inside of the slope top gradually. Keywords: Fluid-Solid Coupling; Damage Failure; Rainfall Intensity; Concrete Dam; Creep Slip; Safety Factor

Management of chemical health hazard fumes emitted during and after embalming procedure and its impact on medical students and embalmers

Abstract: The process of human cadaveric preservation uses diverse embalming formulas introduced in cadavers by means of various technical approaches. Successful embalming requires the use of adequate formulas and techniques to fulfil a long-term structural preservation and minimize shrinkage and any harmful toxic effects to personal and environment. Our aim in this study is to generate a high-quality embalming formula that generate superior embalming and to minimize chemical toxic fumes emitted that students and embalmers are exposed to. An altered low formaldehyde based formula was used in our laboratories and introduced in cadavers through arterial injection using gravity infusion pressure. Results indicate an even distribution of the formula observed exhibiting superior tissue quality and excellent joint flexibility. Final formaldehyde concentration within the embalmed cadavers was minimal. The ambient fumes detected were significantly reduced when compared with other formula’s used complying with international permitted values. There was significant reduction in the symptoms the students complain about during and after contact with cadavers. We conclude that this modified formula yields a higher quality preserved cadavers with high flexibility and colour preservation. A reduction of the unwanted ambient hazardous toxic effects of formaldehyde and other chemical fumes was achieved. Key-words: Formaldehyde, cadavers, exposure, embalming, environment,

Urban Sustainability and Expansion Organization in Middle Eastern City Regions: The Case of Cairo and Amman

Abstract: Major Middle East city-regions have experienced considerable physical, economic and social transformations during the past three decades. The rapid pace of globalization and economic restructuring has resulted in these city-regions receiving the full impact of urbanization pressures. In an attempt to ease these pressures, city-regions such as Dubai, Masqat, Beirut, Amman, and Cairo have advocate expansion organization approaches giving particular interest to urban sustainability. These approaches promote efforts to achieve the triple bottom line sustainability by balancing economic and social development, and environmental protection, and putting (more emphasis on compact and optimum development of urban forms. This paper evaluates the case of two Middle East city-regions, Cairo and Amman, and assesses their experiences in managing their urban forms whilst promoting sustainable patterns of urban development. The findings show that sustainable urban development initiatives employing a top down approach has yielded encouraging results in these case study city-regions. However the need for a more concerted effort towards the overall sustainability agenda still remains vital. Keywords: Sustainable urban development, expansion organization, compact urbanization, city-regions, Cairo, Amman, Middle East

Interstate Water Dispute and Federalism: Governance of Interstate River Water in India

Abstract: Interstate water dispute stands at the juncture of two fields of law: federalism under constitutional law, and water law. Because India is a federal democracy, and because rivers cross state boundaries, constructing efficient and equitable mechanisms for allocating river flows has long been an imperative legal and constitutional subject. The provisions of the Constitution relating to interstate water dispute give a good instance of co-operative federalism. In India water is primarily falls under State list, except in case of interstate rivers where the Central government can intervene. However, powers of the river board created under River Boards Act, 1956 only have advisory powers. There have been instances where States have refused to accept the decision of tribunals rendering the arbitration not binding, which makes the Indian water dispute settlement mechanisms further ambiguous and opaque. The paper examines the methods and policies used before independence to tackle the problem of interstate river water dispute. The paper highlights a need for quick movement to arbitration or adjudication in case of a conflict. The paper presents some recommendations, including the setting up of an independent federated institution to adjudicate and negotiate between the parties to the dispute within a fixed time period. Keywords: Interstate, River, Constitution, Federalism, Adjudication

Comparisons of Procurement Characteristics of Traditional and Labour-Only Procurements in Housing Projects in Nigeria

Abstract: Procurement characteristics of Traditional and Labour-only are compared in some selected states of Nigeria. The objective of this study is to examine if procurement risks, generation of claims, variations to original design, control of sub-­contractors and procurement prospects are the same for both methods. The study obtains its primary data through the use of designed questionnaires that are sent to clients, contractors and consultants. In all, 120 questionnaires were sent to these respondents who recently completed their housing projects based on the two methods. Results of the study indicate that there is no significant difference between both methods in terms of risks of value for money, getting good satisfaction, generation of more claims and variation to original design while a significant difference exists between both methods in risk of timely completion of project. Labour-only method demonstrates less risk of timely completion of project than the Traditional method. Characteristics of both methods are not significantly different from each other when control of sub­contractors, benefits of getting good quality material and workmanship, satisfaction with co-ordination and planning. improved relationship between project team and timely delivery of project are benefits of comparisons. Labour-only differs significantly from Traditional method in terms of prospect of getting good value for money spent on the project. This study concludes that there are various types of risks inherent in use of both methods in housing projects and Labour-only method indicates characteristics of early completion of project and prospects of getting good value for money. Recommendations of the study are that clients, contractors and consultants should use Labour-only for execution of their future housing projects and also they are at liberty to use any of the two methods as they best satisfy their requirements. Implications of this study to policy makers and other stakeholders in the construction industry is that Labour-only method should be explored for use in large and complex projects as significant cost savings can be achieved, timely delivery of project and good value for money are equally achievable with the use of the method. Results of this study serve as a springboard for further research in perfecting the use of Labour-only method for construction projects. Keywords: Comparisons, Procurement characteristics, Traditional and Labour-only procurements, Nigeria.

Effect of PH on Geotechnical Properties of Laterite Soil Used in Highway Pavement Construction

Abstract: Laterite is one of the major materials used in highway pavement construction in Nigeria. Its properties are affected by some environmental factors which may make it unsuitable for highway pavement construction. This research was aimed of investigating the effect of pH on geotechnical properties of Laterite soil used in highway construction. Laterite soil sample was collected from a burrow pit at LAUTECH and it was sun dried for about 24 hours and then soaked in different pH solutions (pH =3.0, pH=5.0, pH = 7.0 and pH= 9.0) using diluted tetraoxosulphate (vi) acid (H 2 SO 4 ) and ammonia. The container was perforated at the bottom in order simulate the actual field condition. The soil samples were taken from soaked sample at 14, 28, 42, 56, 70 and 84 days for sun drying and subsequent laboratory tests. The original and treated samples were subjected to the following laboratory tests: Sieve analysis, Liquid and Plastic limits, Plasticity index, British standard compaction and California bearing ratio. The results showed that the pH of the solution has strong influence on the geotechnical characteristics of the Laterite soil when compared with the original soil sample. This influence caused reduction on the strength properties of the soil and thereby rending it unsuitable for highway construction. Keywords: Laterite, pH, consistency limits, California bearing ratio,

Sustainability of Residential Buildings in Nigeria: An Appraisal of the Factors that Influence Maintenance of Residential Buildings’ Standards

Abstract: Sustainability issues in residential buildings in many cities of the world and the search for factors that influence the level of maintenance of residential buildings, with appropriate measures to assist in the solutions to the problems of building maintenance has been an issue of concern, most especially to the house designers and developers in Niger State, Nigeria. This paper therefore planned to determine factors that influence the level of maintenance of residential buildings’ standards. The research method employed was descriptive and inferential survey. The data collected were subjected to uni-variate analysis and multi-variate analysis, using Statistical Package for Social Sciences (SPSS). The study found among others that factors that influence the level of maintenance of residential buildings standards includes, (i) building’s state of repair, (ii) building type and (iii) Owners/Occupiers highest level of education. The paper concludes that for any meaningful approach to maintainability of residential buildings in view of adequate provision of descent accommodation for the populace, Government and other stakeholders needs to embark on public enlightenment campaign for the residential buildings’ owners/occupants on the need for residential buildings and building premises maintenance and the implication for failure to maintain buildings and buildings’ premises regularly. Keywords: Appraisal, building standards, maintenance, residential building, sustainability.

Monitoring and Modeling of Fayoum Distribution Networks According to Trihalomethanes Formation

Abstract: This paper aimed to predict THMs con. in water networks having multiple feeding sources. Results showed that the THMs con. in all the selected points in the distribution network of Fayoum, Egypt was less than the maximum acceptable con. A statistically-based empirical models were developed for predicting THMs formation under different condition. The first model was developed to predict THMs con. at the exit of the conventional WTPs with R 2 = 0.83. The second model was developed to predict THMs con. at the exit of the Direct filtration WTPs with R 2 = 0.842. The third model was developed to predict THMs con. for water supply networks having one feeding source with R 2 = 0.856. The fourth model was developed to predict THMs con. for water supply networks having multi-feeding sources with R 2 = 0.555. Furthermore, WaterCad program was used to predict THMs con. at FWSN with 1.55 day -1 THMs growth rate. Keywords: Trihalomethanes, Disinfections by-products, Distribution networks

Properties of Pumice Lightweight Aggregate

Abstract: The use of Lightweight concretes has gained acceptance and popularity world wide in the recent years in the construction and development of both the infrastructure and residential buildings The properties of volcanic pumice lightweight aggregates obtained from Longonot in Mai Mahiu area in Kenya was experimentally investigated and this study presents the experimental results of the investigation Three samples of the lightweight aggregates were investigated and their properties compared with those of the conventional normal aggregate In this experimental investigation the physical and mechanical properties of the aggregates were investigated Properties such as bulk density, water absorption, grading and aggregate impact crushing value were determined Keywords : Pumice; Lightweight Aggregate, Bulk Density, Grading

Management of Building Collapse in Nigeria: A Lesson from Earthquake-Triggered Building Collapse in Athens, Greece

Abstract: Recent scientific outputs most especially those published by the Nigerian Building and Road Research Institute (NBRRT) have drawn the attentions of researchers and Nigerian government to the myriad of building collapse and a need for the development of realistic and sustainable approach for the management of building collapse in Nigeria. Since then, a number of different explanations of how and why buildings collapsed in Nigeria have appeared. However, none of these have adequately focused on the most important issue, namely ‘what structural mechanisms led to the state which triggered the collapse’. In this paper, a case study of structural failure in the European monumental city of Athens where European model for the management of building collapse is fully implemented is considered. Structural Analysis Program (SAP) and pi-Design were used for the aseismic investigation and retrofits of the building. The result obtained from the analysis showed that the reduction in the stiffness and resulting friction of the ground floor slabs, and the load bearing columns were the main causes of the building collapse. The European methodology for the management of building collapse proved efficient. It provides the basis for developing countries to develop their own models for the management of building collapse. Keywords: Management, building collapse, structural mechanisms, aseismic investigation, retrofits, stiffness, friction

A Sustainable Supply Chain Model of Manufacturer-Buyer Relationship in Export Oriented Furniture Industry in Indonesia

Abstract: Furniture made from teak wood has an important role in Indonesia’s economic growth It has contribution to boost country income from export and to provide high employment for community However many obstacles occur as challenges that must be overcome by this industry Beside limited supply of high quality teak wood and production inefficiency as the main problems, furniture industry also faces sustainability problem in their activities Export destination countries impose strict requirement for furniture exporters to comply with social and environmental issues This paper proposes sustainability supply chain management model that considers economic, social, and environmental factors In solving the problems, we use goal programming method because the model consists of several conflicting objectives that must be satisfied simultaneously A numerical trial is used to illustrate how the model can satisfy the goals The results can be used to analyze the trade-off among several set of alternative solutions Keywords: Export oriented furniture industry, sustainable SCM, goal programming, manufacturer-buyer relationship