In ultrasonic A‐scan technique the depth and the size of the defect in the material can be determined from the position and amplitude of the reflected echo on the cathode ray tube…
Abstract
Purpose
In ultrasonic A‐scan technique the depth and the size of the defect in the material can be determined from the position and amplitude of the reflected echo on the cathode ray tube screen. However, the main difficulty in ultrasonic testing is the precise recognition of the defect type. The purpose of this paper is to develop analysis software to interpret defects of single‐v butt‐welded mild steel plates in ultrasonic testing.
Design/methodology/approach
This paper establishes a relationship between types of defects in single‐v butt‐welded mild steel plates and the corresponding amplitudes and widths of echo signals, defect positions and beam directions.
Findings
Using this relationship it develops analysis software named “ULTRASL‐1” to predict the type of unknown defects by minimizing the effect of the size and geometry of defect on echo amplitude which is the main limitation in using echo amplitude for identification of defect type.
Research limitations/implications
This paper limits for defects like slag, isolated pore, porosity, lack of inter‐run fusion, lack of side‐wall fusion, crack and lack of penetration in single‐v butt‐welded mild steel plates.
Originality/value
The significance of this work is the introduction of a specialized procedure and a software programme to identify type of defect, so that non‐destructive testing personnel with any level of experience can share the expertise of the best operators in the industry. Hence, it will support to reduce one of the main problems concerning ultrasonic testing, i.e. the difficulties in recognition of defect type.
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S. Thirunavukkarasu, B.P.C. Rao, G.K. Sharma, Viswa Chaithanya, C. Babu Rao, T. Jayakumar, Baldev Raj, Aravinda Pai, T.K. Mitra and Pandurang Jadhav
Development of non‐destructive methodology for detection of arc strike, spatter and fusion type of welding defects which may form on steam generator (SG) tubes that are in close…
Abstract
Purpose
Development of non‐destructive methodology for detection of arc strike, spatter and fusion type of welding defects which may form on steam generator (SG) tubes that are in close proximity to the circumferential shell welds. Such defects, especially fusion‐type defects, are detrimental to the structural integrity of the SG. This paper aims to focus on this problem.
Design/methodology/approach
This paper presents a new methodology for non‐destructive detection of arc strike, spatter and fusion type of welding defects. This methodology uses remote field eddy current (RFEC) ultrasonic non‐destructive techniques and K‐means clustering.
Findings
Distinctly different RFEC signals have been observed for the three types of defects and this information has been effectively utilized for automated identification of weld fusion which produces two back‐wall echoes in ultrasonic A‐scan signals. The methodology can readily distinguish fusion‐type defect from arc strike and spatter type of defects.
Originality/value
The methodology is unique as there is no standard guideline for non‐destructive evaluation of peripheral tubes after shell welding to detect arc strike, spatter and fusion type of welding defects.
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Morteza Ghaseminezhad, Aref Doroudi, Seyed Hossein Hosseinian and Alireza Jalilian
Voltage fluctuation (flicker) is a power quality disturbance that can produce several undesirable effects on industrial equipment. This paper aims to present the methodology and…
Abstract
Purpose
Voltage fluctuation (flicker) is a power quality disturbance that can produce several undesirable effects on industrial equipment. This paper aims to present the methodology and results of investigations undertaken to examine the speed and torque of an induction motor (IM) under voltage fluctuation conditions.
Design/methodology/approach
The IM response to different characteristics of voltage fluctuations is presented. It will be shown that under a special condition the IM torque can even reach two times the rated torque. To show how this occurs, a qualitative discussion is given on the motor response by linearized equations.
Findings
The small-signal analysis was used to determine the frequency which leads to maximum speed fluctuations. It was shown that, if the motor is excited with a modulation frequency (resonant frequency) which is one of its natural frequencies (modes), the mode will act as a fluctuating amplifier and greatly increase the amplitude of torque and speed fluctuations. Sensitivity analysis is also carried out to evaluate the influence of motor parameters on the resonance frequency. The results show that the resonance frequency is not affected at all by the changes in magnetizing reactance. This has been shown that magnetic saturation does not have any impact on the resonance frequency. The most effective parameters are rotor and stator resistances.
Originality/value
With the increasing popularity and use of arc furnace loads in the metallurgy industry and due to the wide application of large IMs in the industry, it is possible that the frequency of torque pulsation locates near a natural frequency and then will create an oscillation with a large magnitude, potentially leading to accelerated fatigue or severe damage of shaft. However, if this phenomenon occurs in industries, the resonance frequency must be filtered from the input voltage. Experimental results on a 1.1 kW, 380 V, 50 Hz, 2 pole IM are used to validate the accuracy of simulation results.
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G.P.P.S. Perera, T.M.M.P. Tennakoon, Udayangani Kulatunga, Himal Suranga Jayasena and M.K.C.S. Wijewickrama
The purpose of this paper is to select a suitable procurement method for steel building construction in Sri Lanka following a systematic method which weigh, both procurement…
Abstract
Purpose
The purpose of this paper is to select a suitable procurement method for steel building construction in Sri Lanka following a systematic method which weigh, both procurement selection factors and existing procurement systems.
Design/methodology/approach
An abductive research stance is followed in this empirical study. Procurement selection factors were selected through a critical literature review which was followed by a quantitative questionnaire survey. The collected data were analysed using descriptive statistical analysis and relative important index.
Findings
The critical literature review outlined 46 procurement selection factors, out of which 26 factors were very important in steel building procurement selection. Short construction period and higher constructability of design are ranked at the top with the highest priority rating factors. Management-oriented procurement system was selected as the most appropriate procurement system for steel building constructions within the Sri Lankan context.
Research limitations/implications
The study is limited to widely use three procurement systems in Sri Lankan construction industry. Yet, the process followed in selecting the most appropriate procurement system could be applied for other contexts. The implications of the study are mainly identifying management-oriented procurement as the most suitable procurement method for steel building construction in Sri Lanka.
Practical implications
The systematic procedure of procurement method selection for steel building construction may use in the Sri Lankan construction industry to limit the resource loss due to wrong selection of procurement.
Originality/value
A study which critically and comprehensively presenting a procurement selection process for steel building construction is not recorded in Sri Lanka prior to this study.
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Abstract
Purpose
Prefabricated construction has been rapidly developing and intensifying the reliance on the supply chain. The pandemic of COVID-19 induced severe disruptions to the supply chain operation and thus attracted the research attention on the supply chain resilience (SCR) under various events. Assessing the resilience of the prefabricated construction supply chain (PCSC) is essential for surviving the shifting disruptive attacks and ensuring consistent, reliable operation. Based on the ripple effect and supply chain performance (SCP), this study aims to develop an assessment model for SCR of PCSC.
Design/methodology/approach
Having identified the roles and material flows among stakeholders, a PCSC network is established. Utilizing the ripple effect model, it develops an assessment framework tailored for PCSCs, which then evolves into a comprehensive assessment model for evaluating the SCR by integrating the disruptive influence and the pre-and post-disruption SCP. Case study is then applied to validate the model.
Findings
Using SCP metrics and disruptive influence assessment as basic dimensions, the SCR can be assessed and expressed through a vector formula. Operating costs and asset utilization can effectively reflect changes in resilience, paying attention to their real-time changes can provide a better judgment of the current stage of disruptions.
Originality/value
The assessment model of SCR accounts for the ripple effect within prefabricated construction, offering a thorough understanding of how disruptions impact the entire supply chain network. Additionally, this model introduces a novel approach to evaluating SCR in reverse by leveraging SCP metrics instead of direct measurement, thereby minimizing potential biases.
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T.M.M.P. Tennakoon, Udayangani Kulatunga and Himal Suranga Jayasena
The purpose of this study is to comprehend the influence of the organisational culture on knowledge management (KM) in an automated construction environment.
Abstract
Purpose
The purpose of this study is to comprehend the influence of the organisational culture on knowledge management (KM) in an automated construction environment.
Design/methodology/approach
An abductive research approach is used, constantly matching theories and observations on KM and organisational culture in testing the influence within a building information modelling (BIM)-enabled environment. A questionnaire survey is used for the primary data collection. Simultaneously, expert interviews are conducted to find the rationale through triangulating data. The primary data analysis is conducted through relative importance index (RII) calculation and content analysis.
Findings
The analysis has declared an increment in the level of influence of culture on KM in a BIM-enabled environment when compared to the conventional construction environment. Coordination and integration, strategic direction and intend and organisational learning are the leading cultural factors that have an increased influence on KM with RII values of 0.8730, 0.8540 and 0.8222, respectively. Because BIM is a technology-infused solution in the construction industry, it can be concluded that technical implementations positively shape the organisational culture to improve the KM process.
Research limitations/implications
The data collection and findings of this research paper regarding the influence of organisational culture on KM are limited to scenarios in the construction industry. Yet, these findings could be implied to similar industries as well, when the KM process is under question.
Originality/value
The study provides the perception of knowledge in terms of the technological implementations such as BIM and organisational culture in the construction industry.
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Tennakoon Mudiyanselage Maheshi Pabasara Tennakoon, Udara Ranasinghe, Aparna Samaraweera, Raufdeen Rameezdeen, Sasanka Gallage, William Robert Newman, Benjamin James White and Delvin Noel Tze Wei Lim
Many work-related factors particularly affect the mental well-being of young construction workers and subsequently affect their productivity at work. Young construction workers in…
Abstract
Purpose
Many work-related factors particularly affect the mental well-being of young construction workers and subsequently affect their productivity at work. Young construction workers in South Australia are more vulnerable than other workers because they consider the distress arising from work-related factors to be part of adapting to a new work life. Therefore, this study seeks to draw out the work-related factors that affect the mental well-being of young construction workers.
Design/methodology/approach
The study employed a sequential mixed method approach including a preliminary qualitative case study and a quantitative survey. Around 20 interviews across two organisations were conducted in the initial case study and content analysis was used to contextualise the factors and identify new factors. Then, the outcome of the case study was fed into a questionnaire survey for further analysis. The survey received 43 valid responses. Principal component analysis (PCA) was performed on the survey outcome to assess and categorise the work-related factors.
Findings
The findings indicate ten prominent work-related factors contributing to poor mental well-being of young construction workers related to three main categories of factors, namely “nature of work”, “task-related stress” and “unsupportive behaviour”. The work-related factors that have the greatest impact on mental well-being are the machoism culture of industry, work overload and workplace bullying.
Originality/value
The outcome from this study enhances the understanding of key work-related factors affecting the mental well-being of young construction workers. Research findings would also help inform the development of clear, industry-informed initiatives tailored to protect and support young construction workers.
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Gihan Anuradha Tennakoon, Raufdeen Rameezdeen and Nicholas Chileshe
The uptake of reprocessed construction materials (RCMs) derived from demolition waste (DW) is limited, which questions the long-term sustainability of DW reverse logistics (RL)…
Abstract
Purpose
The uptake of reprocessed construction materials (RCMs) derived from demolition waste (DW) is limited, which questions the long-term sustainability of DW reverse logistics (RL). To address this gap, the current study focused on identifying informational and structural interventions to promote the uptake of RCMs among Australian construction professionals (CPs).
Design/methodology/approach
Following a qualitative research approach with thirty-one semi-structured interviews, the study explored potential interventions that can drive broader RCM usage. The study's strength lies in the in-depth qualitative insights gathered through extensive interviews with CPs experienced in using RCMs.
Findings
Sixteen informational and structural interventions to promote the uptake of RCMs were identified and mapped against the industry levels at which they should be implemented. RCM suppliers should focus on improving material quality, supply and marketing while minimising material costs. Governments should encourage using RCMs through incentivisation, supportive legislation and approval processes. The significance of awareness building and research was also recognised, which requires the collective efforts of suppliers, governmental and non-governmental bodies and educational institutes.
Originality/value
Despite the talk around sustainable consumption, the actual walk towards this is limited from a construction perspective, as seen through the low uptake of RCMs. This study attempts to bridge this mismatch by outlining informational and structural interventions that would drive CPs to walk the talk and use RCMs for construction applications. While most studies on DW RL have focused on improving waste recovery processes, this study takes a less-trodden path and explores the potential for developing markets for RCMs.
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This chapter seeks to investigate the ways individualistic versus collectivistic values moderate neural responses to social exclusion among African American and White respondents…
Abstract
Purpose
This chapter seeks to investigate the ways individualistic versus collectivistic values moderate neural responses to social exclusion among African American and White respondents. The author hypothesized that the vmPFC – a key brain region for emotion regulation – would correspond to collectivistic value moderation and the dlPFC – the cognitive control center of the brain – would be associated with individualistic value moderation.
Methodology/Approach
This study used a virtual ball tossing game (Cyberball), where 17 African American and 11 White participants were excluded or included with ball tosses, while inside an fMRI scanner. Before the start of each round the participants were primed with individualism, collectivism or a comparison condition.
Findings
Results showed that (1) African Americans showed stronger neural responses to exclusion and (2) offered support for the hypothesis that the dlPFC showed greater activation in African Americans (compared to Whites) when they were primed with individualism values during exclusion. There was no support for the collectivism hypothesis.
Research limitations/Implications
Research limitations included a relatively small sample size (N = 28), a comparison of only two racial groups and that the partners in the game were virtual (pre-programmed by the experimenter).
Practical Implications
This research offers an empirical framework for sociologists seeking to apply social theories into neurological studies.
Social Implications
Identifying effective coping strategies for historically oppressed racial groups.
Originality/Value of Paper
The chapter is original for demonstrating the moderating effects of values on neural responses to exclusion for the first time and by offering a novel neurosociological framework.
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Tennakoon Mudiyanselage Maheshi Pabasara Tennakoon, Nicholas Chileshe, Raufdeen Rameezdeen, J. Jorge Ochoa and Aparna Samaraweera
Offsite construction (OC) is an efficient method to reduce waste in the construction industry from a circular economy perspective. Yet, its uptake is subdued by the ambiguities…
Abstract
Purpose
Offsite construction (OC) is an efficient method to reduce waste in the construction industry from a circular economy perspective. Yet, its uptake is subdued by the ambiguities around its supply chain. Hence, the purpose of this study is twofold: to identify the OC project delivery models, the limitations in their procurement approach to facilitate the resilience of the supply chain and interventions to promote supply chain resilience (SCR) and to identify the gaps in the existing procurement process and propose further research areas that implement strategies to improve SCR.
Design/methodology/approach
The study was conducted as a systematic literature review. In total, 41 peer-reviewed research papers published between 2013 and 2023 were shortlisted through the preferred reporting items for systematic reviews and meta-analysis guidelines. A descriptive analysis was conducted, followed by a thematic analysis.
Findings
The descriptive analysis reveals that the emphasis on digitising OC has shifted to transforming the business model, procurement and supply chain with a human-centric view. In thematic analysis, the predictability of the SC partners and the probabilities of evaluating the prospects are revealed as arbitrary characteristics in the current procurement strategies. Rewarding collaborative relationships among SC partners and incorporating provisions to postpone the module delivery are some interventions to promote flexibility. Drafting comprehensive and effective contracts that address transparency issues and facilitating the need for continuous development of capabilities through procurement are among the further research avenues proposed.
Originality/value
This study is a precursor demonstrating the potential of the procurement process to implement the decrees of SCR for better goal congruence of the OC supply chain.