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The swivel construction method is a specially designed process used to build bridges that cross rivers, valleys, railroads and other obstacles. To carry out this construction method safely, real-time monitoring of the bridge rotation process is required to ensure a smooth swivel operation without collisions. However, the traditional means of monitoring using Electronic Total Station tools cannot realize real-time monitoring, and monitoring using motion sensors or GPS is cumbersome to use.

This study proposes a monitoring method based on a series of computer vision (CV) technologies, which can monitor the rotation angle, velocity and inclination angle of the swivel construction in real-time. First, three proposed CV algorithms was developed in a laboratory environment. The experimental tests were carried out on a bridge scale model to select the outperformed algorithms for rotation, velocity and inclination monitor, respectively, as the final monitoring method in proposed method. Then, the selected method was implemented to monitor an actual bridge during its swivel construction to verify the applicability.

In the laboratory study, the monitoring data measured with the selected monitoring algorithms was compared with those measured by an Electronic Total Station and the errors in terms of rotation angle, velocity and inclination angle, were 0.040%, 0.040%, and −0.454%, respectively, thus validating the accuracy of the proposed method. In the pilot actual application, the method was shown to be feasible in a real construction application.

In a well-controlled laboratory the optimal algorithms for bridge swivel construction are identified and in an actual project the proposed method is verified. The proposed CV method is complementary to the use of Electronic Total Station tools, motion sensors, and GPS for safety monitoring of swivel construction of bridges. It also contributes to being a possible approach without data-driven model training. Its principal advantages are that it both provides real-time monitoring and is easy to deploy in real construction applications.

The construction industry has actively attempted to tackle the low-productivity issues arising from inefficient construction planning. It is imperative to understand how construction practitioners perceive technology integration in construction planning in light of emerging technologies. This study intended to uncover unique experimental findings by integrating 4D-building information modelling (BIM) to virtual reality (VR) technology during construction planning among construction professionals at light steel framing (LSF) projects.

The building industry participants were invited to provide inputs on two different construction planning methods: conventional and innovative methods. The conventional method involved the participants using traditional platforms such as 2D computer-aided design (CAD) and physical visualisation of paper-based construction drawings for the LSF assembly process with a Gantt Chart tool to complete construction planning-related tasks for the targeted project. Comparatively, participants are required to perform the same tasks using more innovative platforms like 4D-BIM in a VR environment.

A Charrette Test Method was used to validate the findings, highlighting an improvement in usability (+10.3%), accuracy (+89.1%) and speed (+30%) using 4D BIM with VR compared to the conventional paper-based method. The findings are also validated by a paired t-test, which is supported by the rationality of the same findings. This study posits positive results for construction planning through the utilisation of modern practices and technologies. These findings are significant for the global construction industry facing low productivity issues, delays and certainty in terms of building delivery timelines due to poor construction planning.

This new blend of technologies—combining 4D BIM and VR in industrialised construction projects—potentially directs future initiatives to drive the efficiency of construction planning in the building lifecycle. The interactive BIM-based virtual environment would purposefully transform construction planning practices in order to deliver modern and more certain building construction methods with a focus on prefabrication processes.

The purpose of this paper is to report and summarize the findings from a doctoral thesis that analyze the construction methods' selection process, from a knowledge management perspective. The first author also reports her PhD journey.

The research methodology is based on the development of case studies in three construction companies. In each case study, semi‐structured interviews, direct observation and review of companies' documentation were applied. The results of the case studies allowed the development of a prototype system for the construction methods' selection. The thesis research methodology is described in detail in this article.

It was concluded that the construction methods' selection process is based in individual knowledge, therefore the construction industry needs to understand how to identify, acquire, store, transfer and use this knowledge. The construction methods knowledge system proposed in this research could help to resolve this problem.

A knowledge management system for construction companies must incorporate knowledge management technologies and techniques to be a real solution for the industry problems regarding information and knowledge management.

This research expands the analysis of the construction methods' selection process with a deeper analysis of this activity, understanding how it is applied in a project, what knowledge is required to make a good decision and offering a system to manage this knowledge, recognizing the particular characteristics of the process and the industry.

With numerous and ambiguous sets of information and often conflicting requirements, construction management is a complex process involving much uncertainty. Decision makers may be challenged with satisfying multiple criteria using vague information. Fuzzy multi-criteria decision-making (FMCDM) provides an innovative approach for addressing complex problems featuring diverse decision makers’ interests, conflicting objectives and numerous but uncertain bits of information. FMCDM has therefore been widely applied in construction management. With the increase in information complexity, extensions of fuzzy set (FS) theory have been generated and adopted to improve its capacity to address this complexity. Examples include hesitant FSs (HFSs), intuitionistic FSs (IFSs) and type-2 FSs (T2FSs). This chapter introduces commonly used FMCDM methods, examines their applications in construction management and discusses trends in future research and application. The chapter first introduces the MCDM process as well as FS theory and its three main extensions, namely, HFSs, IFSs and T2FSs. The chapter then explores the linkage between FS theory and its extensions and MCDM approaches. In total, 17 FMCDM methods are reviewed and two FMCDM methods (i.e. T2FS-TOPSIS and T2FS-PROMETHEE) are further improved based on the literature. These 19 FMCDM methods with their corresponding applications in construction management are discussed in a systematic manner. This review and development of FS theory and its extensions should help both researchers and practitioners better understand and handle information uncertainty in complex decision problems.

Due to the increasing size and complexity of construction projects, construction engineering and management involves the coordination of many complex and dynamic processes and relies on the analysis of uncertain, imprecise and incomplete information, including subjective and linguistically expressed information. Various modelling and computing techniques have been used by construction researchers and applied to practical construction problems in order to overcome these challenges, including fuzzy hybrid techniques. Fuzzy hybrid techniques combine the human-like reasoning capabilities of fuzzy logic with the capabilities of other techniques, such as optimization, machine learning, multi-criteria decision-making (MCDM) and simulation, to capitalise on their strengths and overcome their limitations. Based on a review of construction literature, this chapter identifies the most common types of fuzzy hybrid techniques applied to construction problems and reviews selected papers in each category of fuzzy hybrid technique to illustrate their capabilities for addressing construction challenges. Finally, this chapter discusses areas for future development of fuzzy hybrid techniques that will increase their capabilities for solving construction-related problems. The contributions of this chapter are threefold: (1) the limitations of some standard techniques for solving construction problems are discussed, as are the ways that fuzzy methods have been hybridized with these techniques in order to address their limitations; (2) a review of existing applications of fuzzy hybrid techniques in construction is provided in order to illustrate the capabilities of these techniques for solving a variety of construction problems and (3) potential improvements in each category of fuzzy hybrid technique in construction are provided, as areas for future research.

The use of prefabrication has been considered as one of the most effective waste minimization methods in the construction context; however, the industry has found difficulties to implement it. Contractors lack experience in using prefabrication and they do not know how to implement prefabrication to their projects effectively. The purpose of this paper is to present the findings of a study on the implementation of prefabrication in the context of different project types and procurement approaches.

This paper examines possible project types and procurement methods to maximally gain benefits of using prefabricated building components. A questionnaire survey and structured interviews have been conducted.

From the results, it should be noted that residential projects and design and build procurement methods are the most effective project types and procurement methods, respectively, in using prefabrication. In the interview discussion, one of the governmental employees highlighted that about 65 percent of projects are residential projects. The high supply of residential housing suits fast population growth in Hong Kong. The interviewee also explained that shortening construction period is one of the main goals in their projects. Furthermore, an interviewed main contractor highlighted that the involvement of contractors at the early design stage in a project can bring advantages in considering construction methods before project commencement on site and to improve project constructability. An interviewed subcontractor also explained that the involvement of construction organizations in the design stage can effectively improve the use of prefabrication in major activities including concreting, plastering and formworking, rather than wet‐trade construction activities. Therefore, the use of standardized designs and prefabricated building components are highly encouraged.

This brings early considerations and suggestions to project parties to improve prefabrication implementation. The effects of prefabrication implementation are also considered.

Prefabricated products are continually entering the building construction market; yet, the decision to use prefabricated products in a construction project is based mostly on personal preferences and the evaluation of direct costs. Researchers and practitioners have debated appropriate measurement systems for evaluating the impacts of prefabricated products and for comparing them with conventional on-site construction practices. The more advanced, cost–benefit approach to evaluating prefabricated products often inspires controversy because it may generate inaccurate results when converting non-monetary effects into costs. As prefabrication may affect multiple organisations and product subsystems, the method used to decide on production methods should consider multiple direct and indirect impacts, including nonmonetary ones. Thus, this study aims to develop a multi-criteria method to evaluate both the monetary and non-monetary impacts of prefabrication solutions to facilitate decision-making on whether to use prefabricated products.

Drawing upon a literature review, this research suggests a multi-criteria method that combines the choosing-by-advantage approach with a cost–benefit analysis. The method was presented for validation in focus group discussions and tested in a case involving a prefabricated bathroom.

The analysis indicates that the method helps a project’s stakeholders communicate about the relative merits of prefabrication and conventional construction while facilitating the final decision of whether to use prefabrication.

This research contributes a method of evaluating the monetary and non-monetary impacts of prefabricated products. The research underlines the need to evaluate the diverse benefits and sacrifices that stakeholder face when considering production methods in construction.

Modular integrated construction (MiC) is a modern construction method innovating and reinventing the traditional site-based construction method. As it integrates advanced manufacturing principles and requires offsite production of volumetric building components, several factors and conditions must converge to make the MiC method suitable and efficient for building projects in each context. This paper aims to present a knowledge-based decision support system (KB-DSS) for assessing a project’s suitability for the MiC method.

The KB-DSS uses 21 significant suitability decision-making factors identified through literature review, consultation of experts and questionnaire surveys. It has a knowledge base, a DSS and a user interface. The knowledge base comprises IF-THEN production rules to compute the MiC suitability score with the efficient use of the powerful reasoning and explanation capabilities of DSS.

The tool receives the inputs of a decision-maker, computes the MiC suitability score for a given project and generates recommendations based on the score. Three real-world projects in Hong Kong are used to demonstrate the applicability of the tool for solving the MiC suitability assessment problem.

This study established the complex and competing significant conditions and factors determining the suitability of the MiC method for construction projects. It developed a unique tool combining the capabilities of expert systems and decision support system to address the complex problem of assessing the suitability of the MiC method for construction projects in a high-density metropolis.

Prefabricated technology is gradually being applied to the construction of subway stations due to its characteristic of mechanization. However, the prefabricated subway station in China is in the initial stage of development, which is prone to construction safety issues. This study aims to evaluate the construction safety risks of prefabricated subway stations in China and formulate corresponding countermeasures to ensure construction safety.

A construction safety risk evaluation index system for the prefabricated subway station was established through literature research and the Delphi method. Furthermore, based on the structure entropy weight method, matter-element theory and evidence theory, a hybrid evaluation model is developed to evaluate the construction safety risks of prefabricated subway stations. The basic probability assignment (BPA) function is obtained using the matter-element theory, the index weight is calculated using the structure entropy weight method to modify the BPA function and the risk evaluation level is determined using the evidence theory. Finally, the reliability and applicability of the evaluation model are verified with a case study of a prefabricated subway station project in China.

The results indicate that the level of construction safety risks in the prefabricated subway station project is relatively low. Man risk, machine risk and method risk are the key factors affecting the overall risk of the project. The evaluation results of the first-level indexes are discussed, and targeted countermeasures are proposed. Therefore, management personnel can deeply understand the construction safety risks of prefabricated subway stations.

This research fills the research gap in the field of construction safety risk assessment of prefabricated subway stations. The methods for construction safety risk assessment are summarized to establish a reliable hybrid evaluation model, laying the foundation for future research. Moreover, the construction safety risk evaluation index system for prefabricated subway stations is proposed, which can be adopted to guide construction safety management.

As the population grows, one of the major global crises is the management of human settlement. A proper solution to deal with this issue is mass housing. Given the variable needs in these projects, two constraints of height and volume of construction play an essential role in fulfilling success criteria. Hence, this paper aims to choose the most appropriate building method to satisfy time, cost, quality and safety factors considering the volume and height of construction.

In this research, the proper construction methods in mass housing projects in two volumes of up to 1000 (small) and 1000-3000 (medium) residential units in three ranges of the height of 5, 5-10, and higher than ten floors were determined with a focus on the success criteria based on real experiences through questionnaires and interviews.

The results show that steel bolt and nut and tunnel framework systems in higher than five-floor building projects act better than other methods, while in up to five-floor building projects, LSF saves time and cost and steel bolt and nut provides higher quality and safety.

Given the extent of work, the results of this research can be considered as a benchmark in the mass housing industry.