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The physically-demanding and repetitive nature of construction work often exposes workers to work-related musculoskeletal injuries. Real-time information about the ergonomic consequences of workers' postures can enhance their ability to control or self-manage their exposures. This study proposes a digital twin framework to improve self-management ergonomic exposures through bi-directional mapping between workers' postures and their corresponding virtual replica.

The viability of the proposed approach was demonstrated by implementing the digital twin framework on a simulated floor-framing task. The proposed framework uses wearable sensors to track the kinematics of workers' body segments and communicates the ergonomic risks via an augmented virtual replica within the worker's field of view. Sequence-to-sequence long short-term memory (LSTM) network is employed to adapt the virtual feedback to workers' performance.

Results show promise for reducing ergonomic risks of the construction workforce through improved awareness. The experimental study demonstrates feasibility of the proposed approach for reducing overexertion of the trunk. Performance of the LSTM network improved when trained with augmented data but at a high computational cost.

Suggested actionable feedback is currently based on actual work postures. The study is experimental and will need to be scaled up prior to field deployment.

This study reveals the potentials of digital twins for personalized posture training and sets precedence for further investigations into opportunities offered by digital twins for improving health and wellbeing of the construction workforce.

Work-related musculoskeletal disorders constitute a severe problem in the construction industry. Workers' lower backs are often affected by heavy or repetitive lifting and prolonged awkward postures. Exoskeletal interventions are effective for tasks involving manual lifting and repetitive movements. This study aims to examine the potential of a postural-assist exoskeleton (a passive exoskeleton) for manual material handling tasks.

From an experimental observation of participants, the effects of postural-assist exoskeleton on tasks and workers were measured. Associated benefits of the exoskeleton were assessed through task performance, range of motion and discomfort.

Findings suggest that the exoskeleton influenced discomfort significantly, however range of motion decreased with lifting tasks. The reduced back flexion and increased hip flexion were also indicatives of the participants' responsiveness to the feedback from the exoskeleton. In addition, task completion time increased by 20%, and participants' back pain did not reduce.

The work tasks were performed in a controlled laboratory environment and only wearable inertia measurement units (IMUs) were used to assess the risk exposures of the body parts.

This study opens a practical pathway to human-exoskeleton integration, artificial regeneration or enablement of impaired workforce and a window toward a new order of productivity scaling. Results from this study provide preliminary insights to designers and innovators on the influence of postural assist exoskeleton on construction work. Project stakeholders can be informed of the suitability of the postural assist exoskeletons for manual material handling tasks.

Little has been reported on the benefits and impact of exoskeletons on tasks' physical demands and construction workers' performance. This study adds value to the existing literature, in particular by providing insights into the effectiveness and consequences of the postural-assist exoskeleton for manual material handling tasks.

This study investigates building information modelling (BIM) penetration in quantity surveying (QS) practice by examining the significance attached to the benefits and barriers of BIM adoption, BIM capabilities and future directions of BIM in QS processes. A popular opinion amongst construction researchers is that BIM has the capacity to revolutionize the industry. The study draws-out information in the literature regarding discipline-specific penetration of BIM.

Snowball sampling method was used to obtain information through a survey questionnaire. A total of 73 participants, largely quantity surveyors in Western Australia, took part in the study. Reductionist methodology was used to identify key variables of QS-BIM competencies that are most significant statistically.

BIM does not impose additional difficulties to traditional QS processes. Adherence to standard method of measurement and limited market demand do not hinder BIM deployment significantly. Quantity surveyors are able to use BIM to support their professional services once definitive design models are involved. In addition, the study identifies BIM penetration barriers to include constraints caused by centralised database management and interoperability issues, limitations imposed by market drivers, lack of in-house expertise to manage modelling needs and limited capability in software management.

Future opportunities for skill development are in the areas noted in the findings. Whilst many studies have reported resistance and widespread scepticism amongst some construction disciplines regarding BIM adoption, this study finds BIM penetration in QS practice is considerable, a direction that could trigger further novel innovations.

The methodology reported in the study is novel. In addition, findings from the study inspires other discipline-specific studies to articulate their BIM-penetration trends so that t broad areas of construction can develop a balanced strategy around BIM and innovation development.

Carpenters are constantly vulnerable to musculoskeletal disorders. Their work consists of subtasks that promote nonfatal injuries and pains that affect different body segments. The purpose of this study is to examine ergonomic exposures of carpentry subtasks involved in floor framing, how they lead to musculoskeletal injuries, and how preventive and protective interventions around them can be effective.

Using wearable sensors, this study characterizes ergonomic exposures of carpenters by measuring and analyzing body movement data relating to major subtasks in carpentry flooring work. The exposures are assessed using Postural Ergonomic Risk Assessment classification, which is based on tasks involving repetitive subtasks and nonstatic postures.

The findings of this paper suggest severe risk impositions on the trunk, shoulder and elbow as a result of the measuring and marking and cutting out vent locations, as well as in placing and nailing boards into place.

Because of the type and size of wearable sensor used, only results of risk exposures of four body-parts are presented.

This study draws insights on how to benchmark trade-specific measurement of work-related musculoskeletal disorders. Safety efforts can be targeted toward these risk areas and subtasks. Specifically, results from these will assist designers and innovators in designing effective and adaptable protective interventions and safety trainings.

Extant studies have failed to provide adequate evidence regarding the relationships between subtasks and musculoskeletal disorders; they have only mimicked construction tasks through laboratory experimental scenarios. This study adds value to the existing literature, in particular by providing insights into hazards associated with floor carpentry subtasks.

Construction action recognition is essential to efficiently manage productivity, health and safety risks. These can be achieved by tracking and monitoring construction work. This study aims to examine the performance of a variant of deep convolutional neural networks (CNNs) for recognizing actions of construction workers from images of signals of time-series data.

This paper adopts Inception v1 to classify actions involved in carpentry and painting activities from images of motion data. Augmented time-series data from wearable sensors attached to worker's lower arms are converted to signal images to train an Inception v1 network. Performance of Inception v1 is compared with the highest performing supervised learning classifier, k-nearest neighbor (KNN).

Results show that the performance of Inception v1 network improved when trained with signal images of the augmented data but at a high computational cost. Inception v1 network and KNN achieved an accuracy of 95.2% and 99.8%, respectively when trained with 50-fold augmented carpentry dataset. The accuracy of Inception v1 and KNN with 10-fold painting augmented dataset is 95.3% and 97.1%, respectively.

Only acceleration data of the lower arm of the two trades were used for action recognition. Each signal image comprises 20 datasets.

Little has been reported on recognizing construction workers' actions from signal images. This study adds value to the existing literature, in particular by providing insights into the extent to which a deep CNN can classify subtasks from patterns in signal images compared to a traditional best performing shallow network.

In spite of the benefits of virtual models in the building and construction industry, the full potential of these models, especially in the construction and operation phases, remains largely unrealized. With the increasing developments in information and communication technology, a number of attempts have been made to extend the use of these models, through the development of integration approaches and technologies. However, the issue of integrating the virtual model and the physical construction such as to enable bi-directional coordination, has not been adequately addressed. Thus, the purpose of this paper is to investigate the application of a cyber-physical systems (CPS) approach in enhancing bi-directional coordination between virtual models and the physical construction.

This research employs scenario development rapid prototyping to illustrate CPS integration in the construction industry, with a particular focus on facilitating bi-directional coordination. The proof-of-concept prototype systems developed were validated using a focus group consisting of industry practitioners.

Bi-directional coordination between virtual models and the physical construction has the potential to improve real-time progress monitoring and control of the construction process, tracking of changes and model updates, information exchange between the design office and the job site, real-time documentation of the as-built status of high-value components and improved sustainability practices.

This paper adds value to the construction industry by demonstrating the application of the CPS approach in enhancing bi-directional coordination between virtual models and the physical construction through the development of system architectures, scenarios and prototype systems.

Building information modelling (BIM) offers a new direction of project implementation. It promotes integration of multiple lifecycle stages as well as multidisciplinary integration; whereas conventional approaches are primed on fragmentation. The purpose of this paper is to add to existing debates on the relationship between the rationality of the legal structures underlying fragmented project delivery and BIM’s ability to successfully foster integration across different lifecycle stages. A step further from extant arguments on whether BIM could be sufficiently serviced by the same legal provisions that had serviced fragmented relationships, the study opens up some new fronts regarding the consequences of shared trusts and reciprocity in an integrated project platform.

In addition to a deep analysis of traditional literature on BIM and project management, the study draws its strength from two recent court cases on the limitations of disclaimers against breaches. It also targets court decisions on consequential loss and the duty of care to explain project team’s liabilities when BIM could not live to its theorized promises.

The study shows that disclaimers are a weak protection against liabilities. As BIM offers a dynamic project environment, the study relies on decided cases to show that duty of care to a project (and its owners) is not entirely representable by prototype contract language. More importantly, the study concludes that the applications of BIM to facilities management are better supported on BIM’s new dimension of multidisciplinary integration, rather than a mere coalescing of deliverables across different lifecycle fragments.

This work presents a novel approach to the debate on the potentiality of BIM to drive project success. It adds to the growing discourse on the legal implications of BIM by considering the potential of digital models as a valid and admissible contract instrument.

“Back-to-back” contracts are widely used in the engineering and construction industry and are recently spreading into the telecommunication industry. In back-to-back contracts, the principals require the main contractors to assume majority of the liability in delivering a project and in turn, the main contractors try to allocate most of that liability to their subcontractors. The successful delivery of the projects hinges on how the contracts are drafted and risks are allocated between the parties involved. The purpose of this paper is to undertake a comparative analysis of “back-to-back” subcontracts in the telecommunication and construction industries.

By examining contracting practices and texts from contract documents for the telecommunication and construction industries, this paper reveals how certain aspects of “back-to-back” contracts lose their meaning when seen out of context. Using comparative research method, this paper discusses reasons why the adoption of “back-to-back” contracts should be a matter of degree, based on the business strategy and relevance to the intended transactions rather than on the typical model of “back-to-back” contracts.

Good contracting practices should be such as to enable parties negotiate the contract terms to ensure clarity and common understanding before commencing the project. Construction universally adopts back-to-back even for minor straightforward works, an approach supported by readily available industry model contracts as well as the traditional tender process (design before construction). In telecoms, back-to-back is mainly desired where the subcontractor has a major part of the scope, whereas minor subcontractor scope is considered “leverage commodity” where suppliers are engaged using in-house contract templates, often in a frame contract arrangement, to satisfy corporate strategies for supplier management and pricing.

This paper provides value by presenting an insightful review of the nature of back-to-back contracting practices in the telecommunication and construction industries. The paper outlines advantages, disadvantages and opportunities for improving “back-to-back” contracting practices in the telecommunication and construction industries.