QUALITY MANAGEMENT IN CONSTRUCTION INDUSTRY Role of Construction Manager

ABSTRACT

This paper is a discussion paper on implementation of quality management by construction managers in three Major Australian construction firms. The study examines the importance of quality management of construction project and how the construction managers ensure quality management.  It also takes into consideration the importance of top management commitment towards quality management in the construction industry. This is a qualitative study. Primary data was collected through questionnaire surveys and interviews from 30 construction managers from three construction firms.

The study reveals that as much as the construction managers try to achieve quality management of projects, there are various challenges ranging from, organizational challenges such as lack of top management support of its implementation to unwillingness of construction staff to accept the quality management systems among others. Due to the sample size, and limited time for the research, the study provides areas of further research which can provide generalized results in the context of Australian construction Industry

General Introduction

The construction industry in Saudi Arabia is the largest and fastest-growing market in the Gulf region (Samargandi et al., 2013). Its organisational culture, labour and material supply chain, business strategies, and management skills are different from other parts of the globe. For example, the Kingdom of Saudi Arabia (KSA) has a strong economic standing, which leads its government to take the opportunity to spend money on many public-funded infrastructure projects. The KSA has experienced a construction boom with over 5,200 ongoing public infrastructure projects having a total value equal to US$819 billion (Argaam, 2021). However, Saudi Arabia failed to make real progress in achieving good management and organisational performance as most projects are experiencing delays and cost overruns (Abdellatif and Alshibani, 2019; Mahamid, 2013; Mosley and Bubshait, 2016). A proper QMS development and its practice throughout the project’s life-cycle and its associated organisations are essential to overcome these poor project delivery performances.

Accordingly, Al-Otaibi et al. (2015) discovered that Saudi Arabian construction firms’ performances could be promoted over their counter companies by effectively practising the Total Quality Management (TQM) system. In particular, the TQM has a strong positive correlation improving construction quality culture, which is a critical issue to the project owners. Mazher et al. (2015) studied the effectiveness of TQM in the Saudi construction industry considering four dimensions, such as quality control, management, assurance, and inspection. They applied regression analysis and found quality management and assurance have strong positive significance to the project quality assurance. Aichouni et al. (2014) conducted an empirical study on the adaptation challenges of some already developed quality management systems in the Saudi construction industry. They discovered that organisational culture is the main barrier to implement those tools and techniques in this region. In a further study in Saudi Arabia, Abazid and Gökçekuş (2019) discovered that organisational culture, higher authorities’ willingness to adapt and customize the TQM system, reliability and tangibility dimensions are the main problems in implementing a quality management system. Previous research in other countries also identified that specific company culture, business performance, strategy to quality control, country’s development policy, etc., are distinct and directly linked to the QMS of a company or organization (Bhatia and Awasthi, 2018; Fundin et al., 2018). Thus, a country or company-specific QMS development and practice is a critical need. However, no study in the KSA proposed any QMS model, which can readily be adopted or accommodated local construction issues and culture in construction quality management.

As construction projects usually involve large quantities of resources and many dynamic processes, achieving high quality is end-product-based and depends on managing interrelated organisational processes (Masuin et al., 2020). Among many factors, information system management, quality of reporting documents, recording of quality-related data like inspection, identified issues, and collaboration among the stakeholders to resolve the issues ensuring

intended quality control are significant to develop and practice standard QMS for an organization (Lee et al., 2020; Ma et al., 2018). The mere existence of information management and quality documentation does not necessarily reflect the presence of deep-rooted operational practices and procedures needed for ensuring the ultimate delivery of a well-operated Quality Management System (QMS). Some human factors such as level of learning, building dynamic capability, knowledge integration with a flexible strategy to a product or service are also significant to practice QMS throughout the production supply chain (Gutierrez-Gutierrez et al., 2018). These particular issues, i.e., the company’s culture and strategies to quality assurance, information documentation and management, and human factors in QMS, did not discover any previous study in the KSA. Thus, this paper aims to develop the Quality Management System (QMS) for construction companies in the KSA. In recent years, many researchers have focused on developing and adopting company-based QMS systems using the SERVIQUAL model, TQM, and International Organization for Standardization (ISO) tools (Bhatia and Awasthi, 2018). Towards developing QMS for the KSA construction industry, this study conducted a structured focus group interview with the experts of specific construction companies, followed by two case studies to develop company-specific QMS and its implementation guidelines based on ISO tools

Abstract

Through its sizeable contribution to the country’s Gross Domestic Product (GDP), the construction sector is one of the most important contributors to Nigeria’s overall economy (GDP). The construction sector in Nigeria is plagued with a myriad of issues and roadblocks, many of which cause individual projects to become mired in difficulties and adversely influence overall workflow. Lean construction is a technique that has recently been applied in many nations to solve the majority of the challenges that impede the success of the projects by increasing production above its optimal level, making better use of resources, and getting rid of wastes.
The primary goals of this research are to evaluate the level of knowledge regarding lean construction that is present among engineers who are employed in the construction sector in Nigeria and to determine the elements that have an impact on the workflow of construction projects in that country. The primary purpose of this research is to investigate the obstacles that may be encountered throughout the process of implementing lean construction in Nigeria. In order to establish the issue statement, conduct a literature research, collect and analyze data, and explain the results, the methodology of the study utilized both qualitative and quantitative approaches.
Following the interpretation of the results in light of the theoretical component, the research was finished with a number of results, which are as follows: The vast majority of engineers who are employed in the construction industry in Nigeria are unaware of lean construction, despite the fact that they have a high potential to work in a lean construction site. The main factor that is impacting the workflow of construction projects in Nigeria is the delays in financing the project and in delivery of the materials. The main two challenges that will face the implementation of lean construction in Nigeria are the resistance of the top management to adopt the lean construction methodology, as well as the shortage of skilled labor.

Determining the effect of plastic waste on the properties of hot mix asphalt

Design and construction of precast concrete benches

Abstract

The construction industry in Nigeria is becoming efficient in the area of cost and achieving advance technologies. The effective management of cost enables clients, developers, and facilitators to achieve value for money. Concrete is a major component in every construction project. The use of precast concrete technology has been embraced by the construction industry in Ghana. This study seeks to analyze cost estimating of the structural frame (column and slab) by considering cast-in-place and precast concrete slabs and columns, respectively. Relative importance and Kendall’s concordance agreement were used to determine the rankings and agreement of advantages of using precast concrete. The study established that precast concrete slabs were on average 23.22% cheaper than the cast-in-place concrete elements and precast columns were averagely 21.4% less than cast-in-place concrete columns. The study established that professionals prefer the use of precast concrete products because of the life cycle cost.

Introduction

Concrete material is the most widely used construction material on earth which comprises about 60% of the built environment in many developed countries CCANZ, 2014. Concrete has shaped civilization from as far back as the ancient Egypt and the Roman Empires and it is indispensable in the development of infrastructure, industry, and housing. Without concrete the built environment would fail to accommodate our modern and demanding lifestyle. For concrete the basic building materials provide strength, durability, and even elegance far in excess of many of its manufactured competitors William (2015.)Concrete has a wider range of uses in the construction of commercial buildings, roads, harbours, dams, bridges, electric poles, residential buildings, retaining walls, reservoirs, septic tanks, canals, and a whole lot more M. D. Rahim, S. Mohd, and H. N. Azam (2013). The durability of concrete is of vital importance regarding the life cycle cost of the structure, which includes not only the initial cost of the material and labour but also the cost of maintenance and repair A. Ashworth(2010) .The durability of concrete is therefore defined as its ability to resist weathering action, chemical attack, abrasion, and other forms of deterioration. Concrete has much higher level of fire resistance than other building materials. It is not combustible and would not produce smoke or fuel the fire G. M. E.(2001). Concrete product can be either precast or in situ concrete. This study seeks to analyze the elemental cost comparison of precast and cast-in-place slabs and columns of some selected public projects in Ghana. The construction industry in Ghana is not familiar to the use of precast technology for beams, walls, foundations, and so forth and the precast columns and slabs are the most common in the Nigerian construction industry.

THIS WORK IS N6500

Implementation of protection system used in high power transformer rating protection

CHAPTER ONE INTRODUCTION

The purpose of an electrical power system is to generate and supply electrical energy to consumers. The system should be designed and managed to deliver this energy to the utilization points with both reliability and economy. Many items of equipment are very expensive, and so the complete power system represents a very large capital investment. To ensure the maximum return on the large investment in the equipment, which goes to make up the power system and to keep the users satisfied with reliable service, the whole system must be kept in operation continuously without major breakdowns and also to reduce the impact of fault on the other parts of the system.

 Protection Importance

The importance of the protection lies in two basic points :

1- Detect faults and identifies how serious they are and where are their places. 2- Isolate the affected elements faults and opening the appropriate cutouts.

Protection System a complete arrangement of protection equipment and other devices required to achieve a specified function based on a protection principal.

Protection Scheme: a collection of protection equipment providing a defined function and including all equipment required to make the scheme work (i.e. relays, CT’s, CB’s, batteries, etc ).

Relays are the devices, which monitor the conditions of a circuit and give instructions to open a circuit under unhealthy conditions .

The basic parameters of the three-phase electrical system are voltage, current, frequency and power. All these have pre-determined values and/or sequence under healthy conditions. Any shift from this normal behavior could be the result of a fault condition either at the source end or at the load end .

Transformers are a critical and expensive component of the power system. Due to the long lead time for repair of and replacement of transformers, a major goal of transformer protection is limiting the damage to a faulted transformer. Some protection functions, such as over excitation protection and temperature-based protection may aid this goal by identifying operating conditions that may cause transformer failure. The comprehensive  transformer protection provided by multiple function protective relays is appropriate for critical transformers of all applications.

 Protection relays

A protective relay is the device, which gives instruction to disconnect a faulty part of the system. This action ensures that the remaining system is still fed with power, and protects the system from further damage due to the fault. Hence, use of protective apparatus is very necessary in the electrical systems, which are expected to generate, transmit and distribute power with least interruptions and restoration time. It can be well recognized that use of protective equipment are very vital to minimize the effects of faults, which otherwise can kill the whole system. Relays may be classified according to the technology used :

• Electromechanical relay: They work on the principle of a mechanical force causing operation of a relay contact in response to a stimulus. The mechanical force is generated through current flow in one or more windings on a magnetic core or cores, hence the term electromechanical relay and this relay can be classified into several different types as follows: attracted armature, moving coil, induction, thermal, motor operated, mechanical .

• Static relay: This term implies that the relay has no moving parts, Their design is based on the use of analogue electronic devices instead of coils and magnets to create the relay characteristic. Early versions used discrete devices but advances in electronics enabled the use of linear and digital integrated circuits
• Digital relay: In this type Microprocessors and microcontrollers replaced analogue circuits used in static relays to implement relay functions .

   Statement of problems

Faults occur in substation will eliminate the services from the units for this reason effective protection action is required to minimize damage and repair costs where it senses fault, Ensure safety of personnel.

 Objective 

The main objectives of this research are to develop and investigate protection system used in high power transformer rating protection.

 Methodology

The first stage in this project; numeric relays from ABB techniques used to obtain protection transformer. This protection using ABB REF615 which protect over current, restricted earth fault and differential protection.

On second stage selected setting of numerical According to IEEE Standers and ABB Technical guides.

On final stage run simulation to test the setting.

 Project layout

The thesis is organized as follow :

Chapter one gives brief introduction about relay in protection in electrical network and summarized research objectives and problem.

Chapter  two  contains introduction about    electrical section. Also contains detailed understanding to protect the transformer.

Chapter three contains the of numeric relay Hardware ,Relay interfaces and algorithms.

Chapter four testing of numerical relay with simulation before and after connection to transformer.

Chapter five conclusion and recommendations.

AN ANALYSIS OF THE CAUSES, PREVENTION AND TREATMENT OF DAMPNESS  IN BUILDINGS (A CASE STUDY OF MAKOKO, LAGOS STATE)

INTRODUCTION

Dampness can be defined as water penetration through the walls and certain elements of a building (Halim et al., 2012). Dampness can also be defined as an excessive quantity of moisture contained in building materials and components which causes adverse movements or deterioration and results in unacceptable internal environmental conditions (Briffet, 1994).

Burkinshaw and Parrett (2004) defined dampness as the amount of moisture content present in a material and can be classified as capillary moisture content, equilibrium moisture content, hygroscopic moisture content, total moisture content and potential moisture content. Dampness is the most frequent and main problem in buildings and contributes more than 50% of all known building failures (Halim et al., 2012; Trotman, 2004).

According to Hollis (2000), dampness is inextricably linked to most building deterioration. A source of water close to a building will also be one of the problems associated with dampness. These problems include symptoms such as dirty spots on the building, biological plants like the growth of fungi, mosses and creeping plants, paint flaking, blistering etc. (Halim et al., 2012). In order to successfully diagnose and make appropriate recommendations for remedial actions, one should understand dampness and its impact on buildings.

The ultimate objective of any dampness study is to identify the lead source of moisture in order to recommend actions to remedy the problem (Halim et al., 2012). According to Hollis (2000), sources of dampness can be classified as rising dampness, penetrating dampness, condensation and pipe leakages. According to Burkinshaw and Parrett (2004), dampness can be classified as air moisture condensation, penetrating dampness, internal plumbing leaks, below ground moisture or building specific sources.

Rising dampness occurs as a result of capillary suction of moisture from the ground into porous masonry building materials such as stone, brick, blocks, earth and mortar (Halim & Halim, 2010; Ahmed & Rahman, 2010; Riley & Cotgrave, 2005; Trotman et al., 2004; New South Wales Heritage Office, NSWHO, 2005). The moisture evaporates from either face of the wall (inside or outside), allowing more to be drawn from below. The height to which the moisture will rise is determined by the evaporation rate and the nature of the wall (Halim & Halim, 2010; Ahmed & Rahman, 2010; Trotman et al., 2004; Riley & Cotgrave, 2005; NSWHO, 2005). The normal limit for rising dampness ranges from 0.5 m to 1.5 m above ground level (Halim & Halim, 2010; Ahmed & Rahman, 2010; Trotman et al., 2004; Riley & Cotgrave, 2005; NSWHO, 2005). Rising dampness may show as a high-tide-like stain on wall paper and other interior finishes, and, when it is severe, as blistering of paint and loss of plaster. Damp walls encourage the growth of mold which in conjunction with high humidity, can lead to health problems to occupants (Halim & Halim, 2010; Ahmed & Rahman, 2010; Trotman et al., 2004; Riley & Cotgrave, 2005; NSWHO, 2005).

Water penetration through a building enclosure depends on the simultaneous occurrence of three things: the presence of water; an opening through which water can enter and a physical force to move the water (Beall, 2000). Water can be present as rain, melting snow and soil moisture. Several forces such as gravity, air currents, capillary suction, surface tension, kinetic energy, air pressure and hydrostatic pressure influence the penetration of water into buildings (Beall, 2000). Drips from air conditioning or hot water system overflows, rain water, pipe leakages, water from horizontal directions, etc. can also cause penetration dampness in buildings (NSWHO, 2005). These sources tend to produce small, localized patches of dampness and decay, whereas rising dampness may affect the base of a whole building (NSWHO, 2005).

According to Curtis (2007), dampness resulting from condensation occurs where water in the air inside a building condenses on a cooler surface. This is usually indicative of cold spots in the building, sometimes called cold bridges (Curtis, 2007). It can also occur where there is poor ventilation or where short intense heating cycles do not allow the walls to fully warm up (Curtis, 2007). This situation allows the heated air to hold more water, which condenses when the temperature drops (Curtis, 2007). Excessive condensation frequently results in severe mould growth which can in turn create health hazards. Condensation is one of the most common forms of dampness in residential buildings, mainly caused by warm moist air formed from cooking, washing, bathing or even by just breathing, condensing onto colder surfaces in the homes (Burns, 2010). Damp patches can appear on plaster walls in odd places, particularly on outside walls, often appearing and disappearing on a regular basis (Burns, 2010). Condensation is mostly accompanied by mold which is black in colour but can virtually be of any colour and is very common on walls and ceiling, underneath bay windows, etc. (Burns, 2010). According to the British Research Establishment (BRE), 80-85% of dampness problems in the United Kingdom arise due to condensation or manmade moisture (Ryan, 2002).

There are many visual signs to look out for when diagnosing any damp situation (South Northamptonshire Council, SNC, 2012). In Denmark, rising dampness in the walls of buildings is associated with symptoms such as salt efflorescence, deterioration of rendering and plastering mortar, deterioration of wooden parts of buildings, etc. Condensation is associated with mold growth, usually on top of walls and ceilings (Burns, 2010). Rising dampness may show as a high-tide-like stain on wall paper and other interior finishes, and, when it is severe, as blistering of paint and loss of plaster (Halim & Halim, 2010; Ahmed & Rahman, 2010; Burns, 2010; Curtis, 2007; Trotman et al., 2004; Riley & Cotgrave, 2005; NSWHO, 2005). Mold growth may also be associated with rising and penetration dampness in buildings (Burns, 2010). The 1991 House Condition Survey found that 10.4million homes were affected by mold growth (Ryan, 2002; Wheeler & Critchley, 1998) and the Northern Ireland House Condition Survey in 1996 also found that 16% of homes experienced some form of mold growth (Ryan, 2002).

A STUDY ON FACTORS THAT CONTRIBUTE TO PAVEMENT DETERIORATION/FAILURES

CHAPTER 1: INTRODUCTION

            Background

Universally, all built structures have a limited period of usefulness, meaning every infrastructure is functional only within a time frame after which it begins to collapse. Roads are important infrastructures which are critical to the socio-economic development of countries. Therefore, the road system demands constant maintenance through continuous assessment coupled with real-time repairs to keep them serviceable.

Pavement deterioration is very complex as it involves structural fatigue and functional distresses. The interactions among traffic, climate, material, time and the roadway geometric features account for this distressing phenomenon. It is widely known the huge effect extremely high traffic volumes have on the rapid deterioration of road pavements. In Ghana, huge investments are made in the construction and maintenance of road networks. In 2008 alone, the Government’s expenditure on major rehabilitation and construction was US$ 229 million while US$ 317 million was spent on road maintenance(MoT, 2009).It is therefore essential to develop measures to curtail the high cost of road pavement maintenance as it is the case in Ghana.

The Department of Urban Roads of Ghana has been collecting road inventory and condition survey data for its road development program in all Metropolitan, Municipal and District Assemblies (MMDAs) under its jurisdiction to improve the riding quality of the road network. This also aided the choice of intervention measures required and the maintenance needs of the road network.

The study attempts to investigate the causes of road surface distresses by considering traffic and other road related features in determining the effects of these parameters on road pavement deterioration. Findings will help the Road Authorities to detect the different type of distresses on road pavements earlier and to consequently determine the maintenance needs and activity requirements. This will likewise help the timing of repair or reconstruction, and evaluating the long term financing necessities needed to keep the road functional.

EFFECT OF FLY ASH AND RICE-HUSK ASH ON LIME STABILIZATION OF EXPANSIVE SOILS FROM LOKPAUKWU AND AWGU, NIGERIA

ABSTRACT

Soil stabilization refers to the technique of altering the properties of a soil so as to improve its engineering performance. It aims at using chemical additives such as lime as a lone stabilizer or in combination with industrial residues (fly ash, rice husk ash, etc) to achieve this fit. This work investigates the effects of lime alone, lime-fly ash (LFA) and lime-rice husk ash (LRHA) blends in varying percentage mixtures on the engineering properties of expansive soils from Lokpaukwu (Ezeaku Formation) and Awgu (Awgu Formation) in Lower Benue Trough. The soils were stabilized with different percentages of lime (i.e. 2, 4, 6, 8, and 10%) and varying percentage ratio for lime-fly ash and lime-rice husk ash blends (i.e. 2 : 6, 2 : 8, 2.5:7.5, 2.5 : 10, 3 : 9, 3 : 12, 4 : 12, 4 : 16, 5 : 15 and 5:20).Liquid limit, plastic limit, linear shrinkage, compaction characteristics and California Bearing Ratio (CBR) tests were performed on the natural and lime-treated Lokpaukwu and Awgu soil samples while consistency limits and linear shrinkage tests only were performed on the lime-residue treated soil samples. Results of the study indicate that optimum reduction percentage of 24.14% and 30.56% (liquid limits), 72.22% and 74.42% (plasticity indices), 56.14% and 60.12% (linear shrinkages) and maximum percentage increase of 25.60 and 33.70 (Optimum Moisture Content (OMC)), 193.3 and 250 (unsoaked CBR), and 766 and 700 (soaked CBR) for Lokpaukwu and Awgu samples respectively were obtained on stabilizing the soils with 6% lime content. The results from lime-fly ash (LFA) and lime-rice husk ash (LRHA) blends indicate that liquid limits, plasticity indices and Linear Shrinkages decreased from 58 and 72 to 46 and 51, 36 and 43 to 11 and 12, 11.4 and 14.3 to 6.4 and 7.1, and from 58 and 72 to 45 and 51, 36 and 43 to 10 and 11, 11.4 and 14.3 to 6.4 and

7.1 for Lokpaukwu and Awgu samples respectively when treated with Lime-fly ash blend of 3 – 12% and lime-rice husk ash blend of 3 – 9%.  It could be concluded that improving the characteristics of expansive soils by lime-fly ash blend or lime-rice husk ash blend is successful and provides immense environmental and economic benefits.

CHAPTER ONE INTRODUCTION

• Background of the Study

Soil is the fundamental and most economical of construction materials. It bears the loads of structures and pavements transmitted through foundations and subbases respectively. Researchers have shown that the suitability of a soil as a construction material is a function of its geotechnical properties (Bowels, 1984 and 1988; Head, 1984; Venkatramaiah, 2012). The use of the existing soil at a construction site for engineering purpose may be hindered by poor engineering properties including poor bearing capacity, higher compressibility, and the alternate shrink and swell behaviour of expansive soils.

Expansive soils with potentials to change in volume in correspondence to a change in the moisture or suction condition of the soil (shrink or swell) are normally excluded as engineering construction materials because this volume change causes a resultant deformation, cracking and the eventual collapse of lightweight structures. Incidentally, the collapse of civil structures in some prominent towns in southeastern Nigeria have been associated with the occurrence of expansive clays in these towns (Okeke, 2008; Okeke and Okogbue, 2010)

Improvement of sites with weak or high compressible or high swelling or any other such problematic soils is commonly done by removing the problematic soils and replacing them with more competent ones such as compacted gravel, crushed rock, or lightweight aggregates to increase the load bearing capacity (Kukko, 2000).  Although this is generally accepted as a good solution, the economic feasibility of an alternative construction material may not be guaranteed due to the excessive cost that may be incurred in long distance hauling of the alternative material, excavation of the insitu material and as well as refilling with the alternative material.

Also, rise in global population tends to exert pressure on land which is limited in supply (Oramah, 2006), resulting to a very high demand for the available land and consequent rise in its cost (Rama-Subbarao et al., 2011).  Considering these factors improving the available soil at a site to meet the desired objective becomes the most viable alternative.

Soil improvement can be realized through several methods including the process of stabilization which aims at using chemical additives to achieve this improvement. Cement and lime are the most widely used stabilizing materials. However, the rise in the cost of these industrially manufactured soil improving additives (cement, lime, etc.) with a corresponding increase in the cost of construction on or with cement or lime stabilized soils has led to investigations and the subsequent adoption and usage of industrial wastes (rice husk ash, fly ash, kiln dust, etc.) as alternative materials for the total replacement (i.e. self cementitious e.g, Class C fly ash) or partial replacement (i.e. pozzolans) of cement and lime in engineering constructions (Uzal et al.; 2007; Sata et al. 2007; Yazici, 2008; Okafor and Okonkwo, 2009; Okeke and Enwelu, 2011; Baldino et al., 2014)

Industrial wastes such as fly ash and rice husk ash that accrues from the processing and, utilization of coal and rice abounds in Southeastern Nigeria due mainly to coal deposits and rice cultivation in the area.  Harnessing these industrial wastes as soil treatment materials tend to provide an immense benefit to mankind as it reduces the cost of construction with stabilized soils, and as well as reduction in the environmental hazards caused by these wastes (Muntohar and Hantoro, 2000; Zumrawi and Hamza, 2014).  Therefore, the whole process of soil stabilization with pozzolanic materials is invariably an industrial waste management strategy.

• Problem Statement

The long-term performance of any construction project depends on the soundness of the underlying soils (NLA, 2004).  Expansive soil has been reported as a threat to engineering structures (Ola, 1987; Gutschick, 1967), and to occur mostly and extensively in tropical countries (Holtz and Gibbs, 1956; Katti, 1979; Ola, 1983; Garrido and Castenada, 1992; O’Connel and

Gourley, 1993; Uduji et al., 1994; Okeke, 2008; Lucian, 2008).

Immense damages to civil structures have been attributed to the occurrence of this soil in Nigeria and beyond (Skempton, 1954; Barber, 1956; Youssef et al., 1957; Hammer and Thompson, 1966; Jones and Holtz, 1973, US Army, 1983; Attewell and Taylor, 1984;).  Okeke (2008) reported the occurrence of this problem soil in several towns of Southeastern Nigeria.

On the other hand, industrially developed and emergent nations of the world including Nigeria generate enormous industrial wastes, which constitute environmental hazards.  The utilization of these industrial wastes for soil improvement has been identified as sustainable and cost effective method compared to the conventional method with lime or cement (Rama-Subbarao et al., 2011).  In view of this, this work tends to investigate the stabilization of expansive soils – first with lime and secondly with industrial wastes as percentage substitutes for lime.

• Main Objective

The study aims at utilizing the industrial wastes of Rice-Husk Ash (RHA) and Fly ash (FA) to improve and enhance the geotechnical properties of expansive soils in the study area in relation to their uses in engineering construction, thereby reducing the environmental hazards associated with the wrongful disposal of these wastes.

The specific objectives of the study are to:

• evaluate the effect of lime on the geotechnical characteristics of the expansive soils from Lopkaukwu and Awgu.
• evaluate the influence of rice husk ash on lime stabilization of the expansive soils.
• evaluate the influence of fly ash on lime stabilization of the expansive soils.
• determine the optimum contents for lime, lime-fly ash and lime-rice husk ash admixtures.

• Justification of the Study

There have been cases of structural failures resulting from unstable foundation soils, as well as reports of huge volumes of industrial wastes dumped on open fields, constituting health and environmental hazards. It is against this backdrop that this project was conceived so as to reveal by concrete investigation, the efficacy of these industrial wastes in soil stabilization as an efficient waste management strategy.

Scope of the Study

The Study involved the collection of soil samples and soil additives including lime, rice-husk ash and fly ash.

It was limited to field sampling observations and laboratory analyses of the soil samples with reference to the various additives by measuring the necessary geotechnical properties (parameters); Attterberg limits (liquid limit, plastic limit and plasticity index), linear shrinkage, compaction characteristics (maximum dry density and optimum moisture content), and California bearing ration (CBR).