41 research outputs found
An Assessment of Material Waste Disposal Methods in the Nigerian Construction Industry
No full textThe construction industry is faced with many challenges, among which is waste management. Aside from the fact that wastage contributes to time and cost overrun, it also has environmental implications in the form of pollution. However, the industry has the capacity to effectively manage waste, from generation to disposal. All stages of the management process are important, but scholars and governments have provided the final step, being disposal, unabated attention in order to ensure effective management. Potential waste disposal methods, including incineration, burning, landfilling, recycling, reuse, open dumping, pyrolysis, and shredding have emerged from the literature around the globe. Despite various waste minimisation and sustainable disposal options that are available, construction material waste is still increasing in Nigeria, while disposal remains a major issue for firms and government. Therefore, this study assesses disposal methods among construction firms to determine whether there is a relationship between their practices towards waste disposal. The research followed a concurrent triangulation design in a cross sectional survey, while data were collected via a convergent parallel mixed methods. The quantitative phase employed a structured questionnaire to collect data from 243 building construction firms, while the qualitative phase involved semi-structured interviews with 65 professionals from 10 on-going construction projects in Lagos, Nigeria. The research revealed that landfilling is the most common method of waste disposal, which is closely followed by reuse as backfill and recycling. In addition, the study revealed no association between company’s ownership statuses, age, project specialisation, and disposal methods, except company’s size. In conclusion, the study establishes the need for regulatory policies, such as site waste management plan (SWMP), pay as you throw (PAYT), and landfill ban, which would minimise material waste and divert them from landfills. Recycling and reuse are recommended as sustainable approaches for waste disposal
Rural-Urban Migration in South Western Nigeria: A Menace to National Development
No full textMigration is the movement of people from one place to another which could either be permanent or temporal. The study investigated the resultant effects of rural-urban migration to national development with a particular focus on the South western part of Nigeria. It analyzed the causes of rural-urban migration, past efforts of the government in reducing the rate of rural-urban migration in these areas and the socio-economic factors influencing rural-urban migration. The study also reviewed existing literatures on rural-urban migration. Data were collected from the respondents through a structured questionnaire which was administered on Lagos, Ondo, Ogun, Osun and Ekiti states; all in the southwestern part of Nigeria. The study identified lack of social infrastructure, neglect of the rural community, modernization and others as some of the factors responsible for rural-urban migration. The paper therefore proposes that for all round national development, the rural communities has to be developed to meet the standard of the urban centres in order to reduce the rate of rural-urban migration. Keywords: rural, urban, migration, menace, national development
A review of circular economy development models in China, Germany and Japan
No full textThe circular economy (CE) concept is gaining traction as a sustainable strategy for reducing waste and enhancing resource efficiency. This concept has been adopted in some countries such as Denmark, Netherlands, Scotland, Sweden, Japan, China, and Germany while it is being considered by others including England, Austria, and Finland. The CE has been employed in the manufacturing, agricultural, textile, and steel industries but its implementation varies. It is against this backdrop that this study seeks to identify CE implementation in three pioneering countries (China, Japan, and Germany). A critical review and analysis of the literature was conducted. The results revealed enabling and core policies/laws for the development of the CE concept. It also identified the implementation structure of the CE in China, Germany, and Japan. In conclusion, the findings of this study are expected to serve as a guide for developing and implementing the CE concept in various sectors of the economy
Developing a circular-economy-based construction waste minimisation framework for Nigeria
No full textThe construction industry plays a significant role in developing and developed nation’s growth. It has been criticised as unsustainable because it impacts negatively on the environment and makes onerous demands on natural resources. Therefore researchers, policy makers, governments and non-governmental organisations have recognised the need to promote sustainable construction. Nigeria, one of Africa’s fastest-growing economies and the most populous, is endeavouring to implement sustainable practices. Its construction industry is viewed as lacking sustainable construction approaches such as waste management. The industry is heavily dependent on natural resources and its activities contribute to environmental degradation. A number of studies have identified high volumes of waste and this has highlighted the need for alternative approaches to the current traditional method of construction linked to the linear economy. The circular economy is a concept that integrates material repair, reduction, reuse, and recycling. Although the circular economy has not been applied in Nigeria, it has been adopted in the manufacturing, steel, and agricultural sectors in countries like China, Scotland, and Finland, while others are considering its adoption. The circular economy requires a holistic approach to be effectively and efficiently mainstreamed. Despite its advantages, there has been little investigation of its adoption for the Nigerian construction industry. The aim of this study is to develop a circular-economy-based construction material waste minimisation framework for Nigeria with a view to achieving sustainable construction. The objectives are, first, to identify types, causes, and methods of disposal for material waste. Second, to investigate the awareness, attitudes, and perceptions of Nigerian building construction firms to material waste minimisation. Third, to investigate current approaches to material waste minimisation at the design, procurement, and construction phases. Fourth, to investigate the extent to which the 3R principle has been adopted. Fifth, to identify policies or legislative measures and implementation methods for waste minimisation. Finally, to develop a circular-economy-based construction waste minimisation framework and investigate readiness for its adoption by Nigerian building construction firms. This study is founded on literature about construction waste management, the Nigerian construction industry, construction processes and phases as well as sustainable construction. The concept of the circular economy, including its origins, definitions, principles, characteristics, approaches, drivers, challenges, and benefits have been reviewed. The foundations of the circular economy and theoretical perspectives underpinning its integration have also been reviewed. This study has been viewed from a pragmatic philosophical stance that encourages the use of methods appropriate for the problem. A convergent parallel mixed methods approach was employed to obtain primary data from building construction firms in Lagos, Nigeria. Using a concurrent triangulation design, data obtained from a questionnaire survey were triangulated with data from semi-structured interviews and direct observation. Secondary data were collected via a traditional literature review. Quantitative data were analysed using SPSS. The tests conducted are the relative importance index analysis, factor analysis, Kruskal-Wallis test, and the Spearman’s rank correlation. Qualitative data were analysed through thematic analysis using NVivo 11 to identify key themes, relationships, coding, and sorting into categories. To ensure reliability and validity of the questionnaire data, a Cronbach’s Alpha test was conducted, with a result of 0.83 indicating good reliability and validity. A rigorous process, including a review of the research problem, design, and interview questions, as well as six rechecks of interview transcripts, ensured reliability and generalisability of the qualitative data. Findings suggest that concrete, timber products, and offcut tiles are the main types of waste generated in the Nigerian construction industry. The causes of these types of waste at the design, procurement, and construction phases are design changes, substandard materials, and quality of supervision, respectively. Nigerian building construction firms demonstrate a high level of awareness of the effects of material waste, while exhibiting positive attitudes to waste minimisation. However, their perceptions vary, although the majority perceived environmental protection as an important factor for waste minimisation. The relationships between the Nigerian building construction firms’ awareness, attitudes, and perceptions indicate that these are influenced by their perceptions. Furthermore, the study reveals that design for material optimisation is the design approach most frequently embraced to minimise waste, while design for reuse and recycling is the least frequently used. The most significant procurement approach adopted by the Nigerian building construction firms is to purchase durable materials. A factor analysis of procurement approaches was conducted, and two factors labelled “act green” and “buy green” were extracted. For construction approaches, stock control, effective team work, and avoiding excavation of unnecessary soil were identified as the most important processes, while factor analysis of construction approaches yielded three factors, namely: strategies, techniques, and operations. These approaches to waste minimisation differ among medium and large-scale construction companies. Additionally, the research has revealed reuse of formwork and scaffolding as the most significant approach of the 3Rs principle (reduce, reuse, and recycle). A factor analysis of the 3Rs approaches to waste minimisation yielded three factors, labelled “reduce”, “reuse”, and “recycle”. Site waste management planning is considered by Nigerian building construction firms as the most important policy to minimise waste. Two factors labelled “recommended” and “required” policies were extracted from the factor analysis of policies and regulations for ease of description and understanding. The key implementation methods are policy and education/training of the construction workforce. However, more than half of the firms surveyed do not have an organisational policy on waste minimisation, while 89.3% were keen to adopt a new waste minimisation method. Following these findings, a circular-economy-based construction waste minimisation framework was developed based on the diffusion of innovation theory. The framework consists of five sections, which are: identification of waste minimisation needs, assessment of existing minimisation measures, policy identification and formulation, identification of implementation methods, and evaluation of the proposed framework. This study has established a framework that can be used as a baseline for waste minimisation in the Nigerian construction industry while contributing to gaps identified in the body of knowledge. Adoption of the framework by Nigerian building construction firms and the Nigerian construction industry in general has the potential to reduce waste generated and landfilled. Recommendations are made for policy, training and education, changes in organisational culture and attitudes, best practices, and research and development. The study concludes by identifying future research areas
The circular economy in the construction industry: From research to practice
No full textThe transition to the circular economy (CE) in the construction industry requires a shift from conventional researcher’s roles and thinking styles. The shift is crucial for an industry, which is known for its massive waste generation and resource use globally. The need for collaboration skills cannot be over-emphasized since many CE initiatives involve several stakeholders with diverse interests and approaches to problem solving. It is crucial that CE researchers contribute to the development of theories that are relevant to social issues as well as science in order to enable real-world societal changes and to fast-track the transition to a circular construction sector
A Review of Circular Economy Development Models in China, Germany and Japan
No full textThe circular economy (CE) concept is gaining traction as a sustainable strategy for reducing waste and enhancing resource efficiency. This concept has been adopted in some countries such as Denmark, Netherlands, Scotland, Sweden, Japan, China, and Germany while it is being considered by others including England, Austria, and Finland. The CE has been employed in the manufacturing, agricultural, textile, and steel industries but its implementation varies. It is against this backdrop that this study seeks to identify CE implementation in three pioneering countries (China, Japan, and Germany). A critical review and analysis of the literature was conducted. The results revealed enabling and core policies/laws for the development of the CE concept. It also identified the implementation structure of the CE in China, Germany, and Japan. In conclusion, the findings of this study are expected to serve as a guide for developing and implementing the CE concept in various sectors of the economy
Challenges of Green Building In Nigeria: Stakeholders’ Perspectives
No full textGreen building has become a trend in recent years in an effort to improve the well-being of its inhabitants, community, environmental health, and life-cycle cost. The system's added benefits are the driving force behind the call to use it. Increased acceptance and adoption of green building systems in developed countries have increased awareness in many developing countries, particularly in Africa. As a result, the Green Building Council of Nigeria (GBCN) was established to regulate, monitor, and promote the use of green buildings in Nigeria. Unfortunately, because there are few or no green buildings in Nigeria, adoption has been slow. The aim of this research is to identify the challenges of green building in Nigeria from the perspective of stakeholders, as well as to assess the criticality of each obstacle. To achieve this aim, 86 stakeholders in the construction industry, including government representatives, clients, and professionals, were polled using a series of questionnaires. The findings indicate that the challenges differ depending on the stakeholder. Nonetheless, the common challenges were a lack of understanding and awareness about the economic benefits and opportunities of green buildings, insufficient government support, inaccessible legislation, and the perception that green buildings are expensive. The study recommends that the government take the initiative and lead in proactively preparing the country's urban landscape for green buildings
Enhancing Disaster Resilience: A Review of Public-Private Partnership Models for Secondary Hazard Risk Transfer
No full textDisasters, whether natural or man-made, often result in cascading secondary impacts that exacerbate direct damages and losses. While governments at different levels bear most of the response and recovery costs, the increasing frequency and severity of disasters have stretched public budgets, suggesting the need for collaboration with the private sector. However, innovative risk transfer instruments involving private capital markets have emerged globally to help governments and communities better manage expenditures related to secondary hazards. Therefore, this study reviews public-private partnership (PPP) models to identify those that can help transfer risks associated with secondary hazards. Through a systematic review of literature sourced from academic databases (Scopus, Science Direct, and Google Scholar), reports, and case studies, the study identifies and narratively analyses different PPP models used internationally to transfer multi-hazard and indirect risks out of publicly funded reconstruction programs. The study found that some PPP models for risk transfer, including parametric insurance, index-based insurance, catastrophe bonds, resilience bonds, and risk-sharing agreements, are effective mechanisms for enhancing resilience, promoting financial stability, and mitigating the socio-economic impacts of disasters. The findings of the study will contribute to the existing body of knowledge by offering valuable implications for policymakers, practitioners, and researchers seeking to address the complexities of disaster risk management through collaborative approaches, as well as to identify key considerations and potential solutions related to risk transfers in PPPs. The study concludes that effective PPPs need suitable model selection, strong stakeholder engagement, clear communication, and thorough risk management
Managing Fast-Track Construction Project in Qatar: Challenges and Opportunities
No full textFast-track construction projects are becoming increasingly prevalent in the construction industry, particularly where completion time is essential. A high adoption rate in some of the United Arab Emirate countries and the lack of a conceptual understanding of the challenges inherent in such may jeopardize the future sustainability of the construction sector. To make an informed decision about adopting a fast-track construction method, it is necessary to first identify the opportunities and challenges associated with it. Therefore, this study examines the critical challenges impeding the performance of Qatar’s fast-track construction projects. The research findings were analysed and triangulated using a real-life project as a case study and several data sources. The results of the research identified four critical categories of barriers: design and coordination-related, scope or change orders-related, material and equipment-related, and contractual-related barriers. In addition, strategies such as accurate information, constructability assessment, early involvement of operations and maintenance personnel, and the use of an effective change control system were identified for addressing the identified challenges. The findings are beneficial to professionals who are currently operating or planning to undertake construction projects in Qatar or other United Arab Emirate countries. This study recommends that project managers be more attentive to key barriers in order to improve the performance of fast-track projects and to meet clients’ objectives
Factors Affecting Construction Students’ Satisfaction with Grades in Design Courses
No full textThe construction and built environment sector is dynamic. It is made up of professionals who are knowledgeable about design, planning, construction and cost estimation. Design is one of several courses undertaken by construction students. Assessing design drawings is demanding for tutors as the assessment criteria need careful consideration. Assessment results may encourage or discourage students. Their morale may be affected if they feel their efforts have not been rewarded. Achieving a balance between the tutors’ decisions and students’ satisfaction is therefore important. This research sought to identify factors affecting students’ satisfaction with grades in design courses. The study was undertaken among year 3 and 4 architecture students in a Nigerian university. One hundred and twenty students were invited to reply to an online questionnaire. Their responses revealed that most of them were not satisfied with their tutors. They felt that marking was inconsistent. This study identified a range of ways students felt assessment could be improved. Chief amongst these was a suggestion that the same tutors assessed the work of all students (rather than for several tutors to be involved). Based on these issues, the paper suggests ways to balance tutors’ assessments and students’ satisfaction.</jats:p
