Open Access

Article

Article ID: 1509

Potential risk factors affecting cost and schedule performance in the case of construction projects in Dire Dawa city administration and Harari region, Ethiopia

by Yonatan Getachew Zegeye, Mohammadzen Hasan Darsa

Building Engineering, Vol.3, No.1, 2024; 142 Views, 50 PDF Downloads

Construction projects are inherently fragmented and complex, influenced by various risk factors that can significantly affect both costs and schedules. Identifying and prioritizing these risk factors is crucial for enhancing project management and achieving successful outcomes. This research aimed to identify the most significant risk factors affecting construction projects in terms of cost and schedule performance within the Dire Dawa City Administration and Harari Region, considering the perspectives of contractors, clients, and consultants to provide actionable insights for risk mitigation. A comprehensive literature review and pilot survey initially identified 41 risk factors, which were refined through an iterative process to select 42 factors for a detailed questionnaire survey. Additionally, semi-structured interviews were conducted to gather qualitative insights. Data analysis employed mean ratings to identify the top ten risk factors, utilizing Probability Impact (P-I) Matrix and regression techniques to assess each factor’s significance. The results highlighted six critical risk factors among the ten identified as most impactful: inflation, increases in material prices, exchange rate fluctuations, payment delays, poorly coordinated design, and material delays. The findings indicated strong positive correlation values ( R = 0.800 and R = 0.840) in both models, suggesting that as one variable increases, the other tends to increase as well. These insights provide valuable guidance for project managers, emphasizing the need to focus on these critical risk factors to improve cost and schedule management, ultimately enhancing project outcomes and minimizing cost overruns in the region.

Open Access

Article

Article ID: 1459

Appraising the potentials of reusing plastic bottles as building blocks for housing construction at Paipe village Abuja Nigeria

by Mansir Dodo, Abdulmalik Badamasi, Kabir Ibrahim, Narimah Kasim, Zairra Mat Jusoh, Suleiman Musa Garba, Sanusi Gambo

Building Engineering, Vol.3, No.1, 2024; 54 Views, 28 PDF Downloads

Plastic bottles package a multitude of commodities consumed worldwide. Upon consumption of the commodity, the disposed plastic bottles accumulate as waste, having impacts on both the aquatic and terrestrial environment. In a bid to convert such waste to wealth, plastic bottles are creatively reused for different applications, such as pedestrian bridge boats and street furniture, amongst others. Another application of reusing plastic bottles is their serving as building blocks for housing construction. Reports and research in Nigeria confirm the proliferation of plastic bottles littering the environment, which if reused in housing construction has the potential to contribute to achieving both UN Sustainable Development Goals (SDG) 11 (making human settlements sustainable) and 12 (ensuring sustainable consumption and production). Although Nigeria is traced to being the first country in Africa to reuse plastic bottles in housing construction, not much research output exists from practitioners’ experience on the potentials of reusing plastic bottles as a sustainable construction material as practiced in countries like Vietnam, India, and the Philippines, among others. As such, this study investigates the potential factors driving the practice of reusing plastic bottles in Nigeria with a view to ascertaining the satisfaction derived from the practice for sustainable housing construction. Primary data was collected using a structured questionnaire from 41 respondents identified as having experience in using plastic bottles in construction (5 staffs of Awonto Konsult as well as 36 staffs of Brains and Hammers Construction). Data was analysed descriptively using both IBM SPSS Statistics 23 as well as MS Excel to compute the Mean Score as well as the Relative Satisfaction Index (RSI). Only 30 questionnaires were successfully retrieved and fully answered. Amongst the 10 potential factors studied driving reusing plastic bottles, results show that almost all respondents tend to be ‘satisfied’ with both ‘strength and stability’ (having a Mean Value of 4.70 and RSI of 0.94) as well as ‘durability’ (having a Mean Value of 4.50; RSI of 0.90) of buildings built with plastic bottles. These two factors recorded the highest ‘satisfaction’ ratings, leaning towards ‘very satisfied’. Regarding the factor ‘fire resistance’ of buildings built with plastic bottles (having a Mean Value of 3.40; RSI of 0.68), results reveal that 50 percent of the respondents are ‘unsure’ if it is a satisfactory factor driving reusing plastic bottles or not. The study found that the satisfaction ratings of technical and environmental factors have higher appeal to respondents compared to health and safety and also financial factors. It is recommended that Awonto Konsult and also Brains and Hammers Construction invest more in information related to the fire resistance of plastic bottles used in construction because fire outbreaks pose great threats to buildings. Equally, wider empirical research on plastic bottle wastes, if undertaken, could support the development of policies for waste management, particularly in developing countries. This research has the potential to convert waste into wealth in a bid to minimising environmental impacts of disposed plastic bottles as well as contribute to sustainable materials, particularly for rural housing. Since this study was based on a survey, experimental studies of potentials driving the reuse of plastic bottles in housing construction will reveal results that could enable more sustainable housing construction in Nigeria.

Open Access

Article

Article ID: 1739

Effect of natural pozzolana, pozzolanic sand, and basalt on thermal and mechanical properties of green concrete

by Moustafa Wassouf , Jamal Omran, Ali Kheirbek

Building Engineering, Vol.3, No.1, 2024; 143 Views, 33 PDF Downloads

Green concrete, also known as sustainable concrete, is a building material that aims to reduce environmental impact by using natural, recycled, or sustainable materials in its production. One way to achieve sustainability in concrete is to replace cement with pozzolanic materials, which not only reduces the carbon footprint but also improves the performance of concrete and reduces its cost. This study aims to use natural materials that can partially or completely replace cement and conventional aggregates in concrete mixes. pozzolanic gravel (GPoz) replaced coarse aggregate, basaltic sand (SBas) and pozzolanic (SPoz) replaced fine aggregate, while ground pozzolana (PN) replaced cement. This work focuses on the experimentation and simulation of concrete mixes using the four abovementioned materials. 36 cubes were cast to conduct the thermal conductivity test by direct exposure of concrete samples, where an insulated thermal chamber was designed from thermal bricks, equipped with a heat source from the bottom and an empty space for the tested sample from the top, and then the resistance test on simple pressure was conducted for the cubic samples at the age of 28 days. Pozzolanic aggregate, when used in combination with basalt sand, showed greater thermal resistance compared to conventional concrete. Even with the replacement of 50% of the cement with ground pozzolana, we notice an increase in resistance of more than 11%, but with the replacement of basalt sand with pozzolana sand, we notice an increase in thermal resistance of more than 53%. As for the mechanical properties represented by resistance on simple pressure, we notice an acceptable decrease in resistance when replacing cement with pozzolana, with the exception of mixtures containing aggregates and pozzolana sand together, where replacing 50% of the cement with pozzolana increases the resistance on simple pressure by more than 46.4%.

Open Access

Article

Article ID: 1567

Finite elemental assessment of torsional behavior of RC beams having different shear reinforcement

by Warda Jannat Juhin, Raihan Uddin Ahmed, H. M. A. Mahzuz, Md. Ariful Islam

Building Engineering, Vol.2, No.2, 2024; 78 Views, 36 PDF Downloads

In this paper, the torsional behavior of 8 beams in 4 categories with 2 different ultimate concrete compressive strengths (22.92 MPa and 43.47 MPa) was evaluated, and the best alternative of shear reinforcement pattern compared to the conventional non-welded rectangular stirrup beam (NRSB) was determined. 4 types of beams were modeled using SolidWorks, namely—Non-welded Rectangular Stirrup Beam (NRSB), Welded Rectangular Stirrup Beam (WRSB), Normal Welded Warren Truss-shaped Beam (NWWTB), and Flipped Welded Warren Truss-shaped Beam (FWWTB). The dimension and weight of reinforcement were kept the same for all beams. After simulating using ANSYS, it was seen that WRSB specimens had the largest torsional moment capacity, while NWWTB in normal orientation showed marginal improvement compared to NRSB.

Open Access

Article

Article ID: 1510

Fulfilling the potentials of residential solar energy in Egypt

by Atef Badr

Building Engineering, Vol.2, No.2, 2024; 48 Views, 16 PDF Downloads

Energy plays a very important role in Egypt’s economic development, but the country has a gap between its produced energy and the demand of its growing population. Utilization of solar power systems in Egypt could help the country to close this gap and fulfil its national and international obligations. However, since 1980, the focus in Egypt has been on large-scale industrial solar projects. Limited attention is given to smaller systems for typical residential buildings. The aim of this research, therefore, is to highlight the potential of small residential solar systems (SRSS) in Egypt. With the huge number of residential buildings accommodating more than 115 million Egyptians, SRSS could be the unearthed gem of a sustainable source of energy in Egypt. The geographical location of Egypt and climate were used to generate solar data using the Global Solar Atlas application. The amounts of monthly and annual solar irradiations were calculated and analysed to decide the best orientation of the system (facing east, west, north, and south), identify the optimum tilt angle of the system, and determine the size of the solar panels. A case study was used to illustrate the procedures of designing SRSS for a typical residential building in Egypt. The results showed that a 26 kWp SRSS oriented facing the east with an optimum tilt angle between 15° and 30° could produce an annual total output of electricity more than the annual demand of the occupants of the studied residential building. Such a system would fit easily on the roof of the building. It was concluded that the installation of SRSS in Egypt could help the country meet the demand of its ever-increasing population if properly regulated, financed, and managed. It is recommended that Egypt develop and implement policies to make installations of SRSS an attractive choice among homeowners and investors by introducing encouraging incentives and creating a competitive market with affordable SRSS.

Open Access

Article

Article ID: 1451

Fighting for collusive bidding in the construction industry: A text mining-enabled approach

by Xiaowei Wang, Keda Chen, Yuqing Zhang

Building Engineering, Vol.2, No.2, 2024; 89 Views, 35 PDF Downloads

Policy measures are crucial for regulating collusive bidding and are integral to effective governance. However, current research lacks a comparative exploration of strategies to combat collusive bidding through policy. Therefore, this study aims to identify more effective countermeasures by examining policy variations between regions with low and high incidences of collusive bidding. Using Latent Dirichlet Allocation (LDA) topic modeling, the study extracts key themes from these policies, while qualitative analysis highlights differences in approaches. It underscores that integrating electronic and information technology into bidding systems significantly reduces collusive practices. While increasing penalties can deter collusive bidding, achieving desired impacts requires thorough investigation and vigilant oversight. Additionally, strengthening external supervision enhances control over such activities. This study identifies critical governance strategies for addressing collusive bidding and advocates further research into more effective methods within the construction sector.