Assessment of Management-Related Factors Affecting Construction Labour Productivity in Cross River State of Nigeria

Productivity has always been noted as one of the most important factorsaffecting the success and overall performance of every organisation and the role ofmanagement in this matter cannot be overemphasised. This study assesses and comparesthe relative effects of management-related factors on construction labour productivity inCross River State of Nigeria from the perspectives of building craftsmen and projectsupervisors/engineers. A survey research design approach was adopted which involved astratified random sample of 115 building craftsmen and 60 project supervisors/engineers.Data were collected through structured questionnaires and analysed using Mean ItemScore and Spearman Rank Correlation test. The result shows that there is significantcorrelation between building craftsmen’ and project supervisors’/engineers’ perceptionsof the relative effects of management-related factors on construction labour productivity(p = 0.001 > 0.05). In addition, the selected project team members ranked ‘materialmanagement’, ‘quality of site management’, ‘lack of financial motivation system’,‘supervision’, ‘crew size and efficiency’ and ‘firm reputation’ as the first five significantmanagement-related factors affecting construction labour productivity respectively. Thelast two factors tie rank in the fifth position. It is concluded that there is need forimproved management practices in underdeveloped and developing countries of theworld to enhance productivity on construction sites. The study therefore, recommendsthat construction managers should formulate policies incorporating significantmanagement-related factors affecting construction labour productivity as part ofproductivity improvement strategies on construction sites.Keywords: Construction, craftsmen, effects, factors, labour, management, productivity

Learning models for effective propagation of sustainable construction practices in the built environment / Samuel Ekung & Isaac Odesola

The drive to achieve sustainable built environment has made learning new skills relating to Sustainable Construction Practices (SCP) imperative. This study investigated whether learning method can improve uptake of SCP through knowledge enhancement. Using survey research strategy, data from 206 construction professionals in Nigeria were collected and analysed. The results revealed that Andragogy and Experiential learning models strongly correlated SCP transfer requirements, and are therefore, appropriate models to embed SCP within existing ethos in the built environment. The study espoused the critical roles of experience and hands-on-project as prerequisite reinforcements for effective learning of SCP

Material Waste Minimisation Strategies among Construction Firms in South-South, Nigeria

This study examined material waste minimisation strategies practiced by construction firms in the study area, the amount of waste generated and the relationship between them. The data collected were analysed using mean score, Spearman Rank Correlation, Kruskal-Wallis H and Mann-Whitney U tests. It is revealed that the most commonly employed strategies are “ensuring that storage facilities are properly secured before staff leave on a daily basis”; “checking of deliveries for any shortages and/or damages”; and “using materials before expiry date” with mean scores of 4.46, 4.22, 4.20 respectively. A significant variation in the level of material waste generated by different category of firms was confirmed. There is also a significant relationship between the level of minimisation strategies adopted and the waste generated. Based on the R2 values, 18.8% to 49.4% of the material waste generated for all the material types studied could be explained by the material minimisation strategies adopted on site except for stone base with 9.4%. %. The study recommends that the players in the industry should step up efforts towards introducing incentives to motivate labour to minimise material wastage on site and the use of modular design system

Design-Related Causes of Rework and the Performance of Oil and Gas Projects in Nigeria

In recent times, the need to optimize project performance has been on the front burner of International Oil Companies, especially in developing countries. The quest for rework reduction to improve project performance underpins this research. This study assesses the frequency of occurrence of design-related causes of rework and its influence on project performance in terms of cost and time. A survey research design approach was adopted which involved a stratified random sample of 500 contractors and 385 consultants. Data were collected through structured questionnaire and analysed using Mean Item Score, Spearman Rank Correlation test, Kruskal Wallis test and One Sample T-test. The result shows that there is significant correlation between contractors and consultants’ perceptions of the frequency of occurrence of design-related causes of rework. It also shows that design-related causes of rework have significant influence on project time and cost performance. In addition, the project team members ranked errors and omission in design document, ineffective communication between project team members, design changes, lack of site verification by design team and lack of as-built documentation as the top five frequently occurring design-related causes of rework in oil and gas projects. Furthermore, project location does not influence the frequency of occurrence of design-related causes of rework and its impact on the performance of oil and gas projects.  It is concluded that there is need for effective design and quality management practices to enhance oil and gas project delivery. It is therefore recommended that construction professional in the oil and gas industry should implement design management surveillance and constructability reviews during the design phase as these are effective strategies to reduce design-related causes of rework which will lead to improved project performance in the oil and gas sector

Risks of Implementing Sustainable Construction Practices in the Nigerian Building Industry

This study assessed the risks level associated with implementation of sustainable construction practices through a questionnaire survey distributed to 256 building professionals in Nigeria. It identified 47 risk factors with different likelihood of occurrence and magnitude of impacts.  A quantitative risk analysis result based on mean value method and risk prioritisation number showed that the three top-ranked risk factors with highest likelihood of occurrence were unavailability of sustainable materials and equipment, more complex and unfamiliar construction techniques and processes, and high initial sustainable construction costs; whereas the three top-ranked risk factors with highest magnitude of impacts were high initial sustainable construction costs, poor and inefficient communication among project participants, and high cost of sustainable materials and equipment. The criticality index result identified 23 critical risk factors which mostly related to knowledge and awareness, cost, regulatory framework, building materials and socioeconomic issues. However, the Wilcoxon Signed-rank test result indicated that there is significant difference (z = -3.207, p<0.001) between the likelihood of occurrence and magnitude of impacts of the risks factors associated with implementation of sustainable construction practices in Nigeria of which the effect was moderate (r = 0.468). Furthermore, the study revealed that there is no significance difference in the risk level of the risk factors associated with implementation of sustainable construction practices based on the respondents’ roles (p>0.05). The study, therefore, recommended for training of construction practitioners in the multi-risk management approaches and increasing awareness through education on sustainable construction concept for building industry stakeholders. It further recommended for developing of new sustainable and affordable building materials through research institutes like Nigerian Building and Road Research Institute (NBRRI) with appropriate regulatory and policy frameworks for successful sustainable building projects

Influence Of Labour-related Factors On Construction Labour Productivity In The South-south Geo-political Zone Of Nigeria

Construction labour productivity has continued to be investigated because of its importance in national economies. This study assesses and compares the relative effects of labour-related factors on construction labour productivity across the six geographical states that comprise the south-south zone of Nigeria from the perspectives of building craftsmen and project supervisors/engineers. A field survey involving a stratified random sample of 1,138 building craftsmen and 561 project supervisors/engineers was conducted. Data were collected through structured questionnaires and analysed using mean item scores, KruskalWallis H-tests and Mann-Whitney U-tests. The results show that there is no significant influence of labour-related factors on construction labour productivity across geographical states, especially when they seem to be similar in terms of contiguity, linguistics, ethnicity, cultural practices, climate and socio-economic conditions. The two groups of respondents also agreed on the relative effects of labour-related factors on construction labour productivity. This study concludes that, when project locations are similar, labour management practices and productivities do not vary. 13 opportunities related to the management of labour for productivity improvement on building sites were emphasised. The study recommends that improved labour management practices are a potent productivity improvement strategy that will enhance construction labour productivit

Numerical Modeling of Fluid Flow and Thermal Transport in Gravity - Dominated 3D Microchannels

The success recorded by the usage of microchannel in high flux cooling application, has led to several studies aimed at advancement in microchannel fluid flow and heat transfer technology. A recent study area with promising breakthrough is the effects of g ravity on microscale flow. Numerical simulations were conducted to study single phase flow and heat transfer in 3D microchannels. A priori, the 3D models were validated with experimental results and showed agreement. Two different aspects were simulated: f irstly a microchannel with hydraulic diameter of Dh =199 휇푚 for gravity effects on heat transfer. Secondly, gravity effects on friction factor with hydraulic diameter Dh = 1587 휇푚 . The 3D model confirmed the existence of gravity effects and scaled with significant factors previous 2D model predictions. This result realistically presents the potential of microchannel angular orientation as a passive tool for flow optimization and heat enhancement in portable electronics devices and compact - sized biomedic al devices

Magneto-Rotational Augmentation of Bioconvective Transport in Plasma-Nanofluid Flowing through a Penetrable Spinning Disc

The phenomenon of bioconvective transport through the manipulation of motile microorganisms is considered a promising process control technique in several biological processes and microdevices. Inducing convective transport in self-propelling microbes could be tailored to improve mixing, reaction propensity, and concentration transport within the media. This paper examined the combined effect of magnetic and rotational fields on the argumentation of bioconvective transport in the nanofluid-mediated plasma flow. A detailed analysis of the transport and dynamics of reactive forces during bioconvection in a rotary disclike microchannel is presented. The physics of the problem was described by coupled nonlinear ordinary differential equations, which were numerically computed using the spectral relaxation scheme of the spectral homotopy analysis method. It was observed that the imposition of a magnetic field constituted viscous drag in the plasma-nanofluid media, which consequently increases the thermophoretic parameter in the bioconvective flow. It was ascertained that coupled magnetic and rotational effects significantly augmented the motility of microorganisms and translated to growth in momentum and concentration fields which is noticeable in the generation of stretching effect on the bacterium-containing plasma-nanofluid flow. The findings of this study could provide an essential basis for the design of bioreactors, centrifugal microfluidics technologies, and microdevices for use in a broad spectrum of biotechnology

Assessment of Management-Related Factors Affecting Construction Labour Productivity in Cross River State of Nigeria

Productivity has always been noted as one of the most important factorsaffecting the success and overall performance of every organisation and the role ofmanagement in this matter cannot be overemphasised. This study assesses and comparesthe relative effects of management-related factors on construction labour productivity inCross River State of Nigeria from the perspectives of building craftsmen and projectsupervisors/engineers. A survey research design approach was adopted which involved astratified random sample of 115 building craftsmen and 60 project supervisors/engineers.Data were collected through structured questionnaires and analysed using Mean ItemScore and Spearman Rank Correlation test. The result shows that there is significantcorrelation between building craftsmen’ and project supervisors’/engineers’ perceptionsof the relative effects of management-related factors on construction labour productivity(p = 0.001 > 0.05). In addition, the selected project team members ranked ‘materialmanagement’, ‘quality of site management’, ‘lack of financial motivation system’,‘supervision’, ‘crew size and efficiency’ and ‘firm reputation’ as the first five significantmanagement-related factors affecting construction labour productivity respectively. Thelast two factors tie rank in the fifth position. It is concluded that there is need forimproved management practices in underdeveloped and developing countries of theworld to enhance productivity on construction sites. The study therefore, recommendsthat construction managers should formulate policies incorporating significantmanagement-related factors affecting construction labour productivity as part ofproductivity improvement strategies on construction sites.Keywords: Construction, craftsmen, effects, factors, labour, management, productivity