Infrastructure Engineering - Research Publications

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    Evaluating uncertainties to deliver enhanced service performance in education PPPs: a hierarchical reliability framework
    Geng, L ; Herath, N ; Hui, FKP ; Liu, X ; Duffield, C ; Zhang, L (EMERALD GROUP PUBLISHING LTD, 2022-06-20)
    Purpose This study aims to develop a hierarchical reliability framework to evaluate the service delivery performance of education public–private partnerships (PPPs) effectively and efficiently during long-term operations. Design/methodology/approach The research design included development and test phases. In the development phase, three performance layers, i.e. indicator, component and system, in the education service delivery system were identified. Then, service component reliability was computed through first order reliability method (FORM). Finally, the reliability of the service system was obtained using dynamic component weightings. A PPP school example in Australia was set up in the test phase, where performance indicators were collected from relevant contract documents and performance data were simulated under three assumptive scenarios. Findings The example in the test phase yielded good results for the developed framework in evaluating uncertainties of service delivery performance for education PPPs. Potentially underperforming services from the component to the system level at dynamic timepoints were identified, and effective preventative maintenance strategies were developed. Research limitations/implications This research enriches reliability theory and performance evaluation research on education PPPs. First, a series of performance evaluation indicators are constructed for assessing the performance of the service delivery of the education PPP operations. Then, a reliability-based framework for service components and system is developed to predict service performance of the PPP school operations with consideration of a range of uncertainties during project delivery. Practical implications The developed framework was illustrated with a real-world case study. It demonstrates that the developed reliability-based framework could potentially provide the practitioners of the public sector with a basis for developing effective preventative maintenance strategies with the aim of prolonging the service life of the PPP schools. Originality/value Evaluating education PPPs is challenging as it involves long-term measurement of various service components under uncertainty. The developed reliability-based framework is a valuable tool to ensure that reliability is maintained throughout the service life of education PPPs in the presence of uncertainty.
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    Improving Design by Partnering in Engineering-Procurement-Construction (EPC) Hydropower Projects: A Case Study of a Large-Scale Hydropower Project in China
    Liu, Y ; Tang, W ; Duffield, CF ; Hui, FKP ; Zhang, L ; Zhang, X ; Kang, Y (MDPI, 2021-12-01)
    Hydropower, as a renewable energy resource, has become an important way to fit for Chinese long-term energy policy of energy transformation. Engineering–procurement–construction (EPC) has been increasingly adopted for improving hydropower project delivery efficiency in the utilization of water resources and generation of clean energy, where design plays a critical role in project success. Existing studies advocate the need to use partnering for better solutions to designs in EPC hydropower projects. However, there is a lack of a theoretical framework to systematically address design-related issues considering different participants’ interactions. This study coherently examined the causal relationships among partnering, design management, design capability, and EPC hydropower project performance by establishing and validating a conceptual model, with the support of data collected from a large-scale EPC hydropower project. Path analysis reveals that partnering can directly promote design management and design capability and exert an effect on design capability through enhancing design management, thereby achieving better hydropower project outcomes. This study’s contribution lies in that it theoretically builds the links between intra- and inter-organizational design-related activities by systematically mapping EPC hydropower project performance on partnering, design management, and design capability. These findings also suggest broad practical strategies for participants to optimally integrate their complementary resources into designs to achieve superior hydropower project performance.
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    HOW TO GET INTERNATIONAL CONSTRUCTION PROJECTS DELIVERED ON TIME: FROM CHINESE CONTRACTORS' PERSPECTIVE
    Sun, H ; Tang, W ; Duffield, CF ; Zhang, L ; Hui, FKP (VILNIUS GEDIMINAS TECH UNIV, 2022-01-01)
    67.9% of Chinese international construction projects are seriously delayed, which creates the potential for instability in its rapidly growing share of global contracting markets. A greater understanding of the reasons behind the challenges confronting international contractors is urgently required such that improvements can be developed that ultimately will benefit many countries. This study aims to investigate the time performance of international projects in developing countries and to explore the root causes of time overrun. Based on both quantitative and qualitative analysis of 112 case study projects, collected from 12 of the largest Chinse state-owned enterprises (SOEs), this study identifies the distinctive characteristics of three types of projects (late, acceptable, early) classified based on their time performances. It is established that time performance is significantly related to the contractor’s adaptability and project complexity. The results reveal the root causes of construction delays in international project delivery, which provides a structured and in-depth understanding of both internal and external time performance influential factors. The above findings provide sound basis for guiding practitioners in choosing appropriate strategies to improve project time performance, such as encouraging cross-cultural dialogues, integrating global resources and establishing long-term global partnerships with stakeholders.
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    Structural Health Monitoring of Bridges Using Advanced Non-destructive Testing Technique
    Maizuar, M ; Zhang, L ; Miramini, S ; Mendis, P ; Duffield, C ; Wang, CM ; Ho, JCM ; Kitipornchai, S (Springer, Singapore, 2020-01-01)
    This paper presents an integrated framework for structural health monitoring of bridges by using advanced non-destructive testing (NDT) technique in conjunction with computational modelling. First, the structural characteristics of the Eltham Trestle Bridge under train loading were monitored using the combination of the 3D optical measurement system and IBIS-S. The results demonstrate that, in conjunction with computational modelling, the NDT can capture the structural health conditions of the bridge by analysing the natural frequencies and deformation profiles of the critical members of the bridges. Then, the developed framework also takes into account the impact of extreme events (e.g. truck impacts and earthquakes) by using a reliability-based model. Finally, using the Montague Street Bridge as a case study, it shows that proposed framework has the capability of predicting the residual life of a bridge subject to both progressive deterioration and extreme events throughout its service life.
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    Automation in structural health monitoring of transport infrastructure
    Zhang, L ; Herath, N ; Raja, BNK ; Chen, S ; Miramini, S ; Duffield, C (Springer Singapore, 2021-01-01)
    Roads are among the most important assets in the world. Road structure improvements make a crucial contribution to economic development and growth and bring important social benefits. Automation in structural health monitoring allow the accurate prediction of ongoing damage caused by long-term traffic loading. This permits optimal road structure management and ensures the longevity and safety of road structures. This chapter discusses a variety of advanced automation techniques in structural health monitoring of road structures, such as data acquisition, data processing, and life-cycle assessment. It demonstrates that the implementation of automation in road asset management can increase the productivity and extend the service life of road structures, and enhance the durability of crucial road structures and increase transport infrastructure sustainability.
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    Infrared thermography detection of delamination in bottom of concrete bridge decks
    Raja, BNK ; Miramini, S ; Duffield, C ; Sofi, M ; Zhang, L (JOHN WILEY & SONS LTD, 2021-11-13)
    Infrared thermography (IRT) has been widely used in detecting the subsurface delamination of bridge deck. However, IRT inspection on delamination zones of the bridge deck which have limited exposure to direct solar radiation (e.g., the bottom surface of the bridge deck) is rather challenging due to the relatively low thermal contrast (∆T) development in these zones. Therefore, the purpose of this study is to conduct a series of experimental studies in conjunction with numerical modeling for investigating the effectiveness of IRT in delamination detection of bridge deck components which are normally not exposed to direct solar radiation. Specially, the effects of different environmental conditions, thickness of bridge deck, and defect characteristics on the absolute thermal contrast (∆T) development were systematically investigated. The results show that IRT can effectively detect the subsurface delamination of concrete bridge deck located in regions that are not exposed to the direct solar radiation. In addition, the development of detectable thermal contrast (>0.5°C) is much dependent on the rate of change in ambient temperature with a suitable detection period between 8 am and 4 pm. Furthermore, it shows that the value of ∆T increases with the increase of bridge deck thickness and delamination size.
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    A Simplified Methodology for Condition Assessment of Bridge Bearings Using Vibration Based Structural Health Monitoring Techniques
    Raja, BNK ; Miramini, S ; Duffield, C ; Chen, S ; Zhang, L (WORLD SCIENTIFIC PUBL CO PTE LTD, 2021-09-01)
    The mechanical properties of bridge bearings gradually deteriorate over time resulting from daily traffic loading and harsh environmental conditions. However, structural health monitoring of in-service bridge bearings is rather challenging. This study presents a bridge bearing condition assessment framework which integrates the vibration data from a non-contact interferometric radar (i.e. IBIS-S) and a simplified analytical model. Using two existing concrete bridges in Australia as a case study, it demonstrates that the developed framework has the capability of detecting the structural condition of the bridge bearings in real-time. In addition, the results from a series of parametric studies show that the effectiveness of the developed framework is largely determined by the stiffness ratio between bridge bearing and girder ([Formula: see text], i.e. the structural condition of the bearings can only be effectively captured when the value of [Formula: see text] ranges from 1/100 and 100.
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    Managing Interfaces in Large-Scale Projects: The Roles of Formal Governance and Partnering
    Shen, W ; Tang, W ; Wang, Y ; Duffield, CF ; Hui, FKP ; Zhang, L (ASCE-AMER SOC CIVIL ENGINEERS, 2021-07-01)
    Interface management has been viewed as one of the important organizational capabilities to promote coordination and integration among stakeholders in construction project delivery, especially for large-scale projects. This paper examines the role of formal governance, partnering, and organizational boundary activities and their interactions in interface management performance. An integrated framework with consideration of the influence of formal governance, partnering, and boundary activities on interface management performance and associated project outcomes was developed and empirically tested with data collected from 85 large-scale international projects. The results show that formal governance is the dominant determinant of interface management performance and can indirectly influence it through improving partnering and boundary activities. Partnering and boundary activities are also significant antecedents of interface management performance, which, in turn, improves project outcomes of large-scale construction projects. Formal governance and partnering mutually reinforce each other. Interface management performance is positively related to project outcomes in terms of quality, cost, and schedule. This empirical research contributes to the fundamental understanding of the critical factors that govern the interface management performance and, ultimately, the project outcomes. In addition, the outcomes of this study highlighted the broad managerial implications for participants in large-scale projects.
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    A Competency Framework for Construction Engineering Graduates: An Industry Perspective
    ZHANG, X ; TANG, W ; Duffield, CF ; Zhang, L ; Hui, K ; Liu, Y ; Kang, Y (Tempus Publications, 2021-06-20)
    Engineering education plays a key role in training talent engineers to meet the challenges of sustainable development in the construction industry. To address the requirements of construction engineering and sustainable development, a new competency framework was developed based on a systematic literature review. This framework incorporates five categories of competencies, including interdisciplinary knowledge, technical expertise and innovation, identifying and solving problems, managerial capacity, and ethical and professional responsibilities. The framework was validated using a questionnaire survey and eight rounds of interviews. The results suggest that all the five competencies within the proposed framework are important and should be incorporated in the construction engineering education, and this can help graduates deal with sustainability issues in the future.
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    Infrared Thermography for Detecting Subsurface Defects of Concrete Structures
    Khan Raja, BN ; Miramini, S ; Duffield, C ; Zhang, L ; Wang, CM ; Ming, C ; Kitipornchai, S (Springer Singapore, 2020-12-23)
    Delamination is one of the serious types of deterioration in reinforced concrete structures. It could cause concrete spalling, exposed steel bars, and ultimately affects the structural integrity of concrete structures. Infrared thermography (IRT) is a non-destructive technique which could potentially detect the delamination by capturing thermal contrast (∆T) on concrete surface caused by the heat flow disruption within the concrete due to subsurface anomalies. However, the optimum time and environmental conditions for IRT data collection are still unclear. In this study, an experimentally validated numerical model was developed to investigate the effect of a range of environmental conditions and defect characteristics on the IRT inspection outcomes. The results show that, under direct solar irradiation, the total heat flux input plays an important role in the development of thermal contrast ∆T instead of flux rate. Furthermore, delamination depth and size are two critical parameters that affect IRT results.