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Abstract

Information and Communication Technology advancement has made the method of practice across different industries and businesses record fundamental changes in various dimensions and levels. The construction industry is determined to measure up with other industries in this and has since embraced the use of computer software to perform most, if not all of its activities. It is generally known that this software is not cheap and they require special skill to use. This research study is aimed at developing a computerised template for material and labour schedules for some selected items of work in construction using Microsoft Excel. This is an inexpensive way of estimating to save cost while eliminating the traditional method. The study adopted a mixed research method that involved observation of labourers on-site and validation through a questionnaire survey. The personal observation was carried out and labour outputs were recorded which was used together with material constants in developing the bill of material and labour template. The template was validated by practising Quantity Surveyors for ongoing projects and an average of 92% accuracy was recorded. It was concluded that the template can enhance the accuracy of Quantity Surveyors’ estimate of materials and labour for construction projects.

Abstract

The prevalence of cost overrun in project delivery suggests an acute dearth of inclusive understanding of the effect of risks on construction cost estimation. In aberrant to the generic assumptions, customary to inquiries in construction risk researches, this paper appraised critical construction estimating risks. The study evaluated the sources, frequency and significance of construction estimating risks, using data from a questionnaire survey of 206 quantity surveyors in Nigeria. The data were analysed using factor analysis, Fussy Set Theory, Terrell Transformation Index (TTI), and Kruskal Wallis H tests. The results showed that estimating risks are correlate seven principal sources, namely: estimating resources, construction knowledge, design information, economic condition, the expertise of estimator, geographic factor, cost data, and project factors (λ, > 0.70 <1.0). Twenty-nine risk factors likewise emerged critical construction estimation risks (TTI, 69-87 > 65 percent) and the top three were low construction knowledge, inaccurate cost information and changes in government regulations (factor scores > 0.60 > 0.50). The awareness and accurate assessment of these risks into project cost estimation would reduce cost overrun. The study, therefore, recommends synergies between projects’ internal/ external environments for proper scoping of these risks into project estimates.

Abstract

The construction industry is prone to conflicts and disputes due to complexity, competitive environment, and complicated project documents. In this complex environment, members from various professions, each has their goals and desires to secure the most of his own benefits, work together to build a structure. The objectives of this study were to investigate the frequency, causes, and remedies of disputes in the Central Province of Saudi Arabia. The required data were collected, through a questionnaire survey, from 130 contractors and 54 owners located in the Central Province. This study reveals that disputes in the Saudi construction industry are inevitable with a frequency of occurrence exceeds two disputes per month. Project documents, owners, and contractors to some extent are the sources for such disputes. Project documents are poorly prepared with inaccurate specifications, ambiguity in contract wording, contradictions between project documents, unrealistic project duration, the inaccurate bell of quantities (BOQ), and weakness in contract language. Owners cause great disputes through sizable variation orders exceeding allowable limits, changing item descriptions and quantities in BOQ, interfering in the execution of the contract, and delaying responses to requested information/approvals. Contractors cause disputes through poor contract administration. Contractors follow a combined strategy (mitigating disputes and holding only the disputed work area only) and owners either mitigate disputes or hold disputed scopes. Government owners mostly mitigating disputes and, conversely, private owners hold the disputed scope and continue with the rest of the project. This study is believed to contribute to the current body of knowledge in disputes and contractors and owners by providing effective mitigation techniques that will assist them in minimizing the negative impacts of disputes.

Abstract

In today’s world, uncertainty abounds. It is therefore incumbent on managers to take decisions using unbiased considerations in dealing with organizational risks. Often, risk decisions are replete with assumptions and biases, leading to incorrect decisions. Leaders who apply emotional intelligence (EI) skills are better poised to challenge internal biases and assumptions to improve decision-making, but limited empirical evidence exists that accounts for the nexus between EI, leadership styles and risk perceptions of managers. The purpose of the paper was to explore the relevance of the theory of EI in risk-based decision-making, while comparing various leadership styles. The research adopted a questionnaire survey administered to 173 employed individuals. The research hypotheses analyzed the mediating roles of EI and leadership styles in risk perceptions using ‘t’ statistic and where applicable, Chi-square testing. The results of the analysis confirmed the role of EI in filtering deleterious internal biases and confirmed EI’s presence as a success factor in leadership and decision-making. Transformational leaders are, however, more emotionally intelligent and less biased. These attributes allow for the generation of a suitable risk attitude and enhance risk-intelligent decisions as compared to transactional leaders. This study, while being descriptive, is exploratory in nature and opens pathways for further targeted research based on specific EI abilities or traits and various situational risk attitudes.

Abstract

Managing the production costs of construction projects is crucial especially in the aspect of material management. The use of lightweight materials reduces the dead load in structures, thus the reduction in the use of reinforcement and concrete in the foundation. To this end, this study examined the effect of synthetic foam on the properties of stabilized lateritic brick with a view to producing lightweight stabilized laterite brick for use on weak soils with low bearing capacity. Laboratory tests were conducted on the bricks produced to determine the density, compressive strength, and water absorption properties at 7, 14, 21, and 28 days. Preformed foam using synthetic foaming agent was used at 0%, 25%, 50%, 75% and 100% to replace the water in the experiment. One hundred twenty samples of stabilized foamed lateritic bricks were produced at a mixed ratio of 1:4 (cement: laterite) using a 0.6 water/cement ratio. The result showed that the bricks at all percentages of foam content meet up with the minimum requirement of compressive strength of 1.6N/mm2, 2.0N/mm2 and 3.5N/mm2 recommended by the Nigerian Building code, Nigerian Building and Road Research Institute, and the third class brick of the BS 3921:1985 respectively. The water absorption is within the limits of bricks specified in standards as 15%. The highest compressive strength was recorded at 25% foam inclusion (4.839N/mm2) on 28th day hence concluding that foaming agent stabilizes the characteristics strength of laterite bricks and also reduces its density.

Abstract

Stakeholder management (SM) is of utmost importance in ensuring timely project delivery, delivery within budget, to the right quality level and to client’s satisfaction. Private corporate organizations have limited resources and so could not afford project cost or time overrun and other issues that could impact project success. While studies are available that examined factors impacting stakeholder management in public building projects, there is a paucity of research on factors influencing stakeholder management in building projects procured by private corporate organizations; hence this study. The objective of the reported study is to assess the factors influencing SM in building projects procured by private corporate organizations in Southwestern Nigeria with a view to enhancing project delivery. The data for the study were collected using a structured questionnaire survey. Purposive sampling technique was used to select project managers (PMs) and client representatives (CRs) that were involved in the management of building projects procured by private corporate organizations between 2008 and 2017. A total of 106 questionnaires were received from PMs and CRs that responded to the questionnaire survey. The data collected were analysed using mean score (MS) analysis, Student’s t-test and factor analysis. The result shows that the most important factors influencing SM comprise of ‘maintaining good relationships with stakeholders’, ‘addressing stakeholders’ concerns and needs’ and ‘avenue for communicating project impacts’. The further result using factor analysis shows that the factors influencing SM could be categorized into six component groupings of - project relationship, information input, stakeholder estimation, decision-making, sustainable support and external project relationship awareness. The study concluded that project managers need to pay attention to the identified topranking factors in order to achieve improved project delivery.

Abstract

Contractors, among other construction stakeholders, are vital in achieving the set goals of a project. Adequately engaging a capable contractor is an important task for a client. This study aims at determining the reasons for clients contending with contractors that are not committed to health and safety (H&S). The study was conducted through a literature review, a questionnaire was developed and distributed to 286 construction stakeholders in the Nigerian construction industry. Cronbach alpha was used to test the reliability of the questionnaire used for data collection. Mean scores (MSs) were adopted to determine the major factors that influence clients’ selections and factor analysis was used to cluster variables of high inter-correlations. Findings from the survey reveal that H&S is not a clients’ goal or a project value hence, H&S is not viewed as a vital pre-qualification criterion for contractor selection. This results in a poor checklist concerning contractors’ quality assurance and inadequate verification of contractors’ H&S history. Therefore, appointing non-compliant H&S contractors. The findings provide information on the influence clients have respecting H&S as a prequalification criterion and towards construction workers’ H&S. This will enable construction stakeholders to make the right decision in the pre-qualification of contractors.

Abstract

Accidents are common problems on construction sites globally. The occurrence of these accidents usually leads to loss of time and productivity of site personnel, payments for treatment of the injured and burial expenses for the dead. Previous studies identified poor communication of information on Health and Safety as one of the major causes of accidents on construction sites. This study examined and analyzed the strategies for communication. Mean and standard deviations were used to analyze the strategies. The opinions of supervisors and operatives were tested through an independent t-test and Spearman’s rank correlation. Findings revealed project briefings, operating procedures, and safety manuals as the most frequently used communication strategies. No significant differences exist between the two groups of respondents in their rankings. The correlation coefficient revealed a positive relationship. In other words, respondents concurred in their opinions regarding these communication strategies. This paper, therefore, recommends the adoption of significant strategies identified in this study. In addition, future research can be conducted in other countries in order to explore the research area globally.

Abstract

Dynamic development of 3D printing technology contributes to its wide applicability. FDM (Fused Deposition Method) is the most known and popular 3D printing method due to its availability and affordability. It is also usable in design of technical objects – to verify design concepts with use of 3D printed prototypes. The prototypes are produced at lower cost and shorter time comparing to other manufacturing methods and might be used for a number of purposes depending on designed object’s features they reflect. In the article, usability of 3D printing method FDM for designing of technical objects is verified based on sample functional prototypes. Methodology applied to develop these prototypes and their stand tests are covered. General conclusion is that 3D printed prototypes manufactured with FDM method proved to be useful for verifying new concepts within design processes carried out in KOMAG.

Abstract

The aim of the article is to present the results of laboratory analyses determining the content of rare earth elements (REE) in hard coal type 31.1. Coal was extracted directly from the mining excavation located in the Upper Silesian Coal Basin. Mass spectrometry tests with ionization in inductively coupled plasma (ICP-MS), were aimed at the quantitative analysis of the share of REE in coal, taking into account the economic aspects of recovery of these elements. Fine ground hard coal samples and ashes obtained after coal burning were assessed for the rare earth elements concentration. Results of the rare earth elements concentration (lanthanum and cerium) in hard coal are similar in the values obtained in previous tests. The current analyses present higher concentration of europium or neodymium. The article also contains the concept of possible future research work, consisting in the recovery of rare earth elements using, among others, a classifying hydrocyclone.