Diandian Liu

An SCO-enabled logistics and supply-chain management system in construction

AbstractLogistic and supply-chain management (LSCM) is of paramount importance to a construction project but is often problematic. Many researchers see LSCM per se as a web of decisions to be made, and attribute problems to a lack of process and information concurrence. This is exacerbated by fragmentation, discontinuity, and heterogeneity in construction LSCM. The bidirectional information flow remains unachieved in the existing sensing-based systems for construction LSCM. Without panoramically interconnecting to other smart abilities such as an automatic action-taking ability, most existing sensing-based systems are insufficient to realize their full potential in facilitating construction LSCM. Building on previous studies on smart construction objects (SCOs), this paper aims to develop an SCO-enabled system that can enhance concurrence of process and information, with a view to informing better decision making in construction LSCM. It does so by first analyzing the problems in prevailing LSCM practices...

An Optimization-Based Semantic Building Model Generation Method with a Pilot Case of a Demolished Construction

Emerging technologies like massive point cloud from laser scanning and 3D photogrammetry enabled new ways of generating ‘as-built’ building information models (BIM) for existing buildings. It is valuable but also challenging to generate semantic models from point cloud and images in automated ways. In this paper, we present a novel method called Optimization-based Model Generation (OMG) for automated semantic BIM generation. OMG starts from a semantic BIM component dataset and a target measurement such as point cloud, photographs, or floor plans. A fitness function is defined to measure the matching level between an arbitrary BIM model and the target measurement without object recognition. Combinations of digital components are then extensively generated as building models regarding semantic constraints. The fittest model that matches the target measurement best is the result of OMG. The proposed method was demonstrated in reconstructing a 3D model of a demolished building. Advantages of OMG include high-level automation, low requirement on measurement, relationship discovery for components, reusable component libraries, and scalability to new environments.

Smart gateway for bridging BIM and building

Building information modeling (BIM) has been emerging as a digital platform to create, exchange, and manage the information in a construction project. Over the past decades, researchers have explored various techniques, including laser scanning and sensing devices, to keep the BIM up-to-date. Their efforts have been conceptualized as bridging BIM and building (BBB). In the BBB framework, a key component is the smart gateway which is the middleware to ensure information input/out between the physical project layer and the BIM layer. The aims of this research is multifold: (1) to highlight the importance of smart gateway for BBB; (2) to generate the definition of the smart gateway based on existing gateways in other industries; and (3) to describe the essential functions of the smart gateway based on the BBB framework. Theoretically, with four major functions including device configuration and management, data filtering and processing, temporary information storage, and supplementary information input, the proposed smart gateway can significantly facilitate the integration between the physical project information with BIM. Future research will be conducted to develop and implement a prototype of the smart gateway in actual construction projects where multi data-acquisition devices are used.

The Application Scenarios of Smart Construction Objects (SCOs) in Construction

The primary aim of this study is to investigate the application scenarios of smart construction objects (SCOs). SCOs are construction resources (e.g. machinery, device, and materials) that are made “smart” by augmenting them with technologies conferring autonomy, awareness, and the ability to interact with their vicinity. The research starts from a brief review of recent developments of smart technology in different industrial sectors including construction. Based on the definition and properties of SCOs, interviews and site visits are conducted to investigate how SCOs could be applied under different scenarios of the construction industry. Perspectives for future studies are proposed in order to fully realise their potentials. The research encourages a wider adoption of SCOs and smart technologies in improving current construction practices. It also provides academia with a platform for further exploring the innovative uses of SCOs in construction.

A SCO-Based Tower Crane System for Prefabrication Construction

Prefabrication construction has been increasingly applied to the construction industry. Automation and intelligentization of construction site and construction objects has become the fore for the development of the prefabrication construction. In this study, a SCO-based tower crane system, as the core resource site on the critical path of prefabrication construction, is proposed to make the cranes more intelligent and efficient. A set of smart units are applied to the tower cranes and prefabricated components to make them into Smart Construction Objects (SCOs), enabling the functions of awareness, communicativeness and autonomy. The smart tower crane could “talk” with prefabrication components through sensors and real-time wireless connections. A system operation flow is developed for fetching and placing target components. The SCO-based tower crane system can provide the operation instruments, real-time traceability of the components, and necessary warning. The system is being tested in a pilot project, which is delivered through BIM and prefabrication construction. It is envisaged that the SCO-based tower crane system could significantly improve the safety performance and operation efficiency of the tower crane operations in prefabrication construction.

A Physical Internet-enabled Building Information Modelling System For Prefabricated Construction

Prefabricated construction is believed to be energy conserving though opportunities for achieving higher energy efficiency have yet to be fully harnessed. From investigation of a prefabricated construction project in Hong Kong, two main problems have been revealed relating to energy consumption, including: (i) inefficient management of resources such as labours and machines, and (ii) inefficient production, transportation, and on-site assembly of prefabricated components. These problems are primarily caused by lagged information communication and human errors. This paper seeks to offer a solution by developing a Physical Internet-enabled Building Information Modelling System (PI-BIMS) that integrates Auto-ID technologies, BIM, and cloud computing. The PI-BIMS enables real-time collection, communication, and visualisation of information across the processes of production, transportation, and on-site assembly. Practical issues of the system implementation are provided through a pilot prototype. It is found that the PI-BIMS helps enhance the resource allocation efficiency and decrease human errors. Thus, an alternative opportunity to improve energy efficiency in prefabricated construction has become possible.

RFID-Enabled Management System Adoption and Use in Construction: Passing Through the Labyrinth with an Improved Technology Acceptance Model

The development of radio frequency identification (RFID) technologies has drawn notable attentions in recent studies in the construction industry. However, the initiatives of RFID technologies and RFID-enabled management systems are yet to be fully accepted and adopted in practice. The management systems seem caught in a labyrinth whereby technology developers complain that practitioners are notorious to embrace new technologies, while practitioners view the systems ‘disruptive’, if not useless altogether. By collecting qualitative research data from construction practitioners who are actively engaged in a RFID-enabled management platform implementation, this study explores the factors influencing these practitioners for accepting the system. An extended technology acceptance model (TAM) is proposed as a guiding framework to provide a better understanding of these practitioners’ adoption and use behaviors. Findings mesh with extended TAM indicating that ‘perceived usefulness’ and ‘perceived ease of use’ are of major influence to their attitude toward technology adoption. Moreover, the research demonstrates that the construction practitioners’ attitude are changing and heavily affected by the project managers who take the roles of system execution, or by peers who have harvested the benefits of such system. The findings of this study are not designed to be generalized but to offer a new perspective and insights to future TAM studies.

Bridging the Cyber and Physical Systems for Better Construction: A Case Study of Construction Machinery Monitoring and Utilization

It has been widely accepted that developing and maintaining a cyber system (e.g. Building Information Modeling) representing the corresponding physical system is a promising approach to improve decision-making in construction. However, to bridge the bi-directional coordination between the virtual and the physical system is the prerequisite for the improvement, yet this is the most challenging part for researchers and practitioners. Using tower crane as a case study, the primary aim of this study is to propose a cyber-physical system by articulating its system structure, bridging technologies, and its computational applications. Particularly, a smart core is developed to integrate real-time information on physical machinery on site with their ‘cyber twins’ in virtual, which is developed as a web-based platform. A LEGO® tower crane is built and simulated in lab, showing the cyber and physical systems can be well bridged to facilitate safety management and resource utilization in construction projects.