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This material may be downloaded for personal use only. Any other use requires prior permission of the American Society of Civil Engineers. This material may be found at https://ascelibrary.org/doi/10.1061/%28ASCE%29CO.1943-7862.0001630 Recycling concrete waste helps reduce the negative environmental impacts of construction activities. Worldwide, concrete recycling rates and available applications for recycled concrete vary widely. A deep understanding of the current status of concrete recycling in individual countries or regions would allow development of applicable and effective strategies for improvement.

Intro -- Preface -- Contents -- Abbreviations -- Background and Observations -- 1 Introduction -- 1.1 History -- 1.2 Seismo-Atmospheric Anomalies -- 1.3 Seismo-Ionospheric Disturbances -- 1.3.1 Pre-seismic Ionospheric Anomalies -- 1.3.2 Co-/Post-seismic Ionospheric Anomalies -- 1.4 Summary -- References -- 2 Atmospheric Changes and Observations -- 2.1 Atmospheric Structure -- 2.2 Atmospheric Changes -- 2.2.1 Neutral Atmospheric Changes -- 2.2.2 Ionospheric Changes -- 2.3 Observation Techniques -- 2.3.1 Radiosonde -- 2.3.2 Ionosonde -- 2.3.3 Ionospheric Scatter Radar -- 2.3.4 Faraday Rotation Detection -- 2.3.5 MODIS and OLR Observations -- 2.3.6 Electromagnetic Observations -- 2.3.7 GNSS Observations -- 2.4 Solar and Geomagnetic Observations -- 2.5 Seismological Observations -- References -- 3 GNSS Tropospheric Sounding -- 3.1 Atmospheric Refractivity -- 3.2 GNSS Tropospheric Delay -- 3.3 Ground-GNSS Tropospheric Monitoring -- 3.3.1 2-D Tropospheric Monitoring -- 3.3.2 3-D Tropospheric Tomography -- 3.4 Space-Borne GNSS Radio Occultation -- 3.4.1 Refraction Index -- 3.4.2 Calculation of Total Refraction Angle -- 3.4.3 Abel Inversion -- 3.4.4 Inversion of Atmospheric Parameters -- 3.5 Other GNSS RO -- References -- 4 GNSS Ionospheric Sounding -- 4.1 Ionosphere -- 4.2 Ionospheric Delay -- 4.3 Ground-GNSS TEC Estimation -- 4.3.1 GNSS Observation Equations -- 4.3.2 GNSS Ionospheric Observations -- 4.3.3 Cycle Slip Detection -- 4.3.4 2-D Ionospheric Estimation -- 4.3.5 3-D GNSS Ionospheric Tomography -- 4.4 Space-Borne GNSS Ionospheric Monitoring -- 4.4.1 Ionosphere Inversion Based on Doppler -- 4.4.2 Ionosphere Inversion Based on TEC -- 4.4.3 Recursive Inversion of TEC -- 4.4.4 Amplitude Inversion -- References -- 5 Detection Methods for Ionospheric Disturbances -- 5.1 Detection Methods -- 5.1.1 Statistical Probability Method.

Introduction -- Atmospheric Changes and Observations -- Atmospheric Changes and Observations -- GNSS Ionospheric Sounding -- Detection methods for ionospheric disturbances -- Seismic lower-atmospheric anomalies -- Pre-seismic Ionospheric Anomalies -- Co-/Post-seismic Ionospheric Disturbances -- Two-mode seismo-ionospheric disturbances -- Seismo-ionospheric Rayleigh waves -- Epicenter from Ionospheric Disturbances -- Tsunami Ionospheric Disturbances -- Volcano Atmospheric Disturbances -- Volcanic Plumes Detection from GNSS SNR -- Summary and Prospective -- Index

The emerging Building Information Modeling (BIM) can better promote the development of building industrialization, with data integration between information-rich building models and business processes. However, the practical implementation of BIM still faces barriers. Existing studies have discussed these barriers extensively, but the research on the barriers to the implementation of BIM amid building industrialization in China is inadequate. In this study, 23 barriers were identified through literature review. A questionnaire survey approach was used to collect data from various parties. Factor analysis methods were used to process and rank barrier factors for BIM applications in the context of industrialized building. Based on the analysis of each factor, analytic hierarchy process was adopted to identify the key barriers to the implementation of BIM for industrialized building construction. The study concluded that the main barriers for BIM implementation for industrialized building were capital-related factors and the lack of support from owners. This study proposes that in addition to governmental policy support for BIM and multi-stakeholder engagement, companies should also organize experts to effectively evaluate the risks of applying BIM. Overall, this study provides suggestions on construction organizational transformations in the roadmap of moving towards digital-driven building industrialization.

This material may be downloaded for personal use only. Any other use requires prior permission of the American Society of Civil Engineers. This material may be found at https://ascelibrary.org/doi/abs/10.1061/%28ASCE%29EI.1943-5541.0000425 This study extends the existing reviews targeting the Journal of Professional Issues in Engineering Education and Practice (JPIEEP) by incorporating the text-mining review methodology. A total of 1,810 papers published in JPIEEP since 1982 were selected as the literature sample. Dividing the whole sample into four subsamples according to publication time spans, this review indicates that literature published before 2000, especially articles from the 1982 to 1991 period, emphasized more civil engineering–related practical and practical issues (e.g., legislation).

Abstract Purpose The purpose of this paper is to target on individual perceptions of BIM practice in terms of BIM benefits, critical success factors (CSFs) and challenges in Chongqing which represented the less BIM-developed metropolitan cities in China. Design/methodology/approach Adopting a questionnaire-survey approach followed by statistical analysis, the study further divided the survey population from Chongqing into subgroups according to their employer types and organization sizes. A further subgroup analysis adopting statistical approach was conducted to investigate the effects of employer type and organization size on individual perceptions. Findings Subgroup analysis revealed that governmental employees held more conservative and neutral perceptions toward several items in BIM benefit, CSFs and challenges. It was inferred that smaller organizations with fewer than 100 full-time employees perceived more benefits of BIM in recruiting and retaining employees, and considered more critical of involving companies with BIM knowledge in their projects. Originality/value This study contributed to the body of knowledge in managerial BIM in terms that: it extended the research of individual perceptions toward BIM implementation by focusing on less BIM-mature regions; it contributed to previous studies of influencing factors to BIM practice-based perceptions by introducing factors related to organization type and sizes; and it would lead to future research in establishing BIM climate and culture which address perceptions and behaviors in BIM adoption at both individual and organizational levels. Keywords

There is an increase of megaproject construction worldwide. At the same time, risks involved in megaprojects have also become a wide concern. Extending from the macrolevel of qualitative analysis focusing on complexity, politics, and morality, the research conducted the microscopic empirical analysis on twenty-two typical cases by adopting the quality comparative analysis (QCA) from the auditing perspective. Different from the traditional analysis method taking each causation as independent variable, the results in the study revealed that there was complex multiple concurrent causation among eight conditions; additionally, the configuration of those would be divided into six types, among which, the coverage of the three types, namely, project management risk, preliminary and construction risk, and tendering and contract management related risk, was almost eighty percent. Finally, megaproject risks in China were caused by complicated and changeable combination conditions, which would provide a new breakthrough for seeking analyzing megaproject risks through this quantitative analysis method, and indicate the researchers and practitioners to control the megaproject risks from a more systematic way.

This material may be downloaded for personal use only. Any other use requires prior permission of the American Society of Civil Engineers. This material may be found at https://ascelibrary.org/doi/10.1061/%28ASCE%29CO.1943-7862.0001408 Building information modeling (BIM), the emerging digital technology, is undergoing increasing application in developing countries including China. Both the governmental policy and industry motivation have indicated that BIM is becoming the mainstream innovation in China's construction industry. Nevertheless, one major concern lies in the uncertainty of BIM investment for architecture, engineering, and construction (AEC) firms.

The purpose of this paper is to summarize the latest research of BIM adoption in construction engineering and management (CEM) and propose research directions for future scholarly work. During the recent decade, building information modeling (BIM) has gained increasing applications and research interest in the construction industry. Although there have been review-based studies that summarized BIM-based research in the overall architecture, engineering and construction (AEC) area, there is limited review that evaluates the current stage of BIM-based research specifically in the CEM sub-area. Design/methodology/approach CEM falls into the scope of AEC. It involves construction-related tasks, activities and processes (e.g. scheduling and cost estimates), issues (e.g. constructability), as well as human factors (e.g. collaboration). This study adopted a holistic literature review approach that incorporates bibliometric search and scientometric analysis. A total of 276 articles related to BIM applied in CEM were selected from Scopus as the literature sample for the scientometric analysis. Findings Some key CEM research areas (e.g. CEM pedagogy, integrated project delivery, lean and off-site construction) were identified and evaluated. Research trends in these areas were identified, and analyses were carried out with regard to how they could be integrated with BIM. For example, BIM, as a data repository for ACE facilities, has substantial potential to be integrated with a variety of other digital technologies, project delivery methods and innovative construction techniques throughout the whole process of CEM. Practical implications As BIM is one of the key technologies and digital platforms to improve the construction productivity and collaboration, it is important for industry practitioners to be updated of the latest movement and progress of the academic research. The industry, academics and governmental authorities should work with joint effort to fill the gap by first recognizing the current needs, limitations and trends of applying BIM in the construction industry. For example, it needs more understanding about how to address technical interoperability issues and how to introduce the integrated design and construction delivery approach for BIM implementation under the UK BIM Level 2/3 framework. This study contributed to the body of knowledge in BIM by proposing a framework leading to research directions including the differences of BIM effects between design-bid-build and other fast-track project delivery methods; the integration of BIM with off-site construction; and BIM pedagogy in CEM. It also addressed the need to investigate the similarities and differences between academia and industry toward perceiving the movement of BIM in construction field work.

University students are the future driving forces in and leaders of the architectural, engineering and construction (AEC) industry advancement. Although BIM pedagogical studies have been performed in different institutions, there has not been sufficient research providing a global perspective of BIM education and students' perceptions toward BIM practice and application following their learning progress. The purpose of this paper is to adopt student samples from Swinburne University of Technology (SUT, Australia), Wenzhou University (WZU, China) and University of Brighton (UK) as three case studies to investigate the BIM practice and application-related perceptions and motivations. Design/methodology/approach Based on the thorough understanding of the BIM pedagogical delivery including teaching contents and assessment methods among the three institutions, a questionnaire survey approach was adopted to collect AEC students' perceptions of BIM. Within each selected case, statistical analysis was conducted to investigate both the overall sample and subgroup differences regarding students' opinions on BIM's functions (e.g. as a 3D visualization tool) and BIM usefulness in various industry professions, their motivation in BIM-related jobs and their perceptions of challenges encountered in BIM practice and application. Multiple factors influencing BIM learners' perceptions were discussed, such as pedagogical assessment approach, and individual factors (e.g. disciplines). Findings The results showed that students were able to discern the latest industry practices and critical thinking in BIM movements. For example, SUT students perceived more challenges from the government legislation or incentive policies, which was consistent with Australia's BIM policy movement. WZU students tended to have less positive views on BIM usefulness. The results also indicated fewer differences regarding perceived challenges among students from these three institutions. Originality/value This study contributed to the body of knowledge in managerial BIM by focusing on learners' perceptions from the perspective of students' understanding, motivation and individual views of BIM, which were insightful to both BIM educators and employers. By initiating the framework of BIM learning process and its influence factors, the current study serves as a point of reference to continue the future work in strengthening the connection between institutional BIM education and industry practical needs worldwide.

The relatively low level of sustainability of major public projects has been subject to criticism by the community, increasing the pressure to incorporate the concept throughout the project lifecycle and the importance of understanding the perceptions of affected groups. The study undertook this task by compiling a list from the literature of the sustainability concerns that are associated with major public projects from their economic–social–environmental implications, identifying the relevant stakeholder groups in the Guangdong–Hong Kong–Macao Greater Bay Area and their levels of influence by interviews, and evaluating various sustainability objectives from a multi-stakeholder perspective via a questionnaire survey. The results were validated through a series of interviews with purposively selected experts. The study findings indicate the need for more consideration of social concerns in Guangdong province, the proper levels of public participation in Hong Kong in order to avoid excessive interruptions to the pace of project procurement, and that Macao may have to experience a relatively slow development of construction in order to balance the social/environmental requirements that are involved. These findings contribute to both the government and construction industry at large in delivering economically, socially, and environmentally sustainable major public projects in the Bay Area and China as a whole.

The Construction industry is a major player in the UK economy and is in need of continuous improvement. In an attempt to do so, in 2011 the UK government made Building Information Modelling (BIM) level 2 a mandate for all public projects by 2016. Integrated Project Delivery (IPD) is a project delivery approach closely attributed to BIM. However, it does not seem to have received proportionate level of attention and uptake in the UK.

Purpose The purpose of this paper is to target on individual perceptions of BIM practice in terms of BIM benefits, critical success factors (CSFs) and challenges in Chongqing which represented the less BIM-developed metropolitan cities in China. Design/methodology/approach Adopting a questionnaire-survey approach followed by statistical analysis, the study further divided the survey population from Chongqing into subgroups according to their employer types and organization sizes. A further subgroup analysis adopting statistical approach was conducted to investigate the effects of employer type and organization size on individual perceptions. Findings Subgroup analysis revealed that governmental employees held more conservative and neutral perceptions toward several items in BIM benefit, CSFs and challenges. It was inferred that smaller organizations with fewer than 100 full-time employees perceived more benefits of BIM in recruiting and retaining employees, and considered more critical of involving companies with BIM knowledge in their projects. Originality/value This study contributed to the body of knowledge in managerial BIM in terms that: it extended the research of individual perceptions toward BIM implementation by focusing on less BIM-mature regions; it contributed to previous studies of influencing factors to BIM practice-based perceptions by introducing factors related to organization type and sizes; and it would lead to future research in establishing BIM climate and culture which address perceptions and behaviors in BIM adoption at both individual and organizational levels.

Emerging construction practices such as building information modelling (BIM), prefabrication construction, green building, and integrated project delivery methods are gaining momentum in China, with great potential due to the size of its construction market. Through this, the sustainability level of China's construction industry is expected to be enhanced from the economic, social and environmental perspectives. So far, there has been limited understanding of how BIM, as a digital technology, would affect other contemporary sustainable construction practices from the industry professionals' point of view. Limited studies have been carried out to study the regional differences of these contemporary sustainable practices in China. This study adopted a questionnaire-based approach targeting industry professionals from three different metropolitan cities (Shanghai, Guangzhou, and Wenzhou).The follow-up comprehensive statistical analysis revealed that with regards to these contemporary sustainable construction practices, survey participants held much varied views on the growth of renovation projects, traditional Design–Bid–Build delivery, and conventional on-site construction methods. These three types were also generally perceived to have weak correlation with BIM application. Regional comparison further conveyed information on differences in perceptions among survey respondents from these three cities. For example, respondents from Wenzhou perceived more positive effects of BIM use in conventional construction projects. This research addressed the inter-correlation among these emerging sustainable construction practices, as well as the regional differences in China's construction market. The findings provide insights and the big picture for both governmental authorities and industry practitioners on the latest sustainable practices of China's construction industry. Recommendations are also offered towards improved economic, social and environmental sustainability performance for construction projects in the country.