Intact pavement markings organize the utilization of the pavement surface area, increase the road capacity, and improve traffic safety. However, deterioration occurring over the service life will ...lead to traffic safety hazards. A detailed inspection is regarded as the central tenet of pavement marking management. Conventional manual assessment approaches are time-consuming, qualitative, and argued to be subjective. Thus, cost reduction, quantitative analysis, and automatization have been the focus of research. Unmanned Aerial Vehicle (UAV) platform has been studied wildly in civil tasks due to its low cost and high maneuverability. A UAV-based platform was developed in this research to address the inefficiency, access limitations, and image processing of existing road marking inspection systems. In this research, the resolution of the image is 5472 × 3080 pixels and is captured with a fixed focal length of 8.8 mm. Given intensity differences between pixels of paintings and asphalt backgrounds, the pixels belonging to painting regions are classified using the K-mean clustering algorithm. After detecting all parking lines from images, the Otsu method was employed to determine the threshold of 0.9 as the quantitative indicator of painting quality. The UAV-based platform exhibits expected performance in assessing the pavement markings in a parking area. Future research will explore the deployment in city-scale applications.
This paper presents the measured effects of different resource qualities on construction performance. The paper describes a recommended method, proposed with the concept of prediction by ...understanding the causal effect of process resources on consequent work efficiencies. The project team measured and compared the different arrangements of resources and their effects on on-site work efficiencies. The paper includes a field study of 15 operations (40 piles) in Melbourne, on several worksites of prefabricated piles and installations. It aimed to determine the causality between the set of delivered prefabricated piles and relevant work efficiencies. This field includes its purpose of generating and providing scientific evidence in effectively implementing an offsite operation. One of the critical factors affecting the efficiency of the installation process was confirmed to be the location of the longest section in the sequence. It took 21.8 minutes longer with the middle part of the installation if the longest section was designed to be in the middle of the whole prefabricated steel pile. The findings confirmed the need for holistic communication along the supply chain. The originality of this project is to provide a case study that offers archival evidence of the proposed model in a practical situation.
The ever increasing complexity of construction projects asks for improved communication and automated data collection supported by continually improving electronic tools. Advances in information ...technologies enable us to link critical resources on construction sites, such as trucks and cranes, to the project website creating many opportunities to drastically improve productivity, safety and quality. While the use of electronic equipment is nothing new in construction, no model exists to integrate them into one unified framework. This paper presents a wireless site-network concept consisting of information hubs enabled to automatically connect data sinks with sources supported by software agents. Included in this paper is the discussion of a mobile information hub, the eCKiosk, enabled to connect the work crew electronically to the project network while collecting automatically live “as-built” data. It begins with a review of long range wireless as the basis for designing a robust Agile Site Communication Network (ASCNet). Site experiments with short range wireless conduits and embedded RFID tags showed that they are able to provide information far beyond an identification number. While wireless technologies are poised to open totally new avenues to manage construction, more field-tests are needed to establish a solid knowledge base to create a pervasive network for the dynamically changing building site.
•Concept of Agile Site Communication Network (ASCNet) is presented.•The electronic Construction Kiosk (eCKiosk) is the “central gate” of ASCNet.•Long range WiFi and ZigBee e-links were studied to secure ASCNet applicability.•Embedded RFID tags were tested to assure reliable short range e-communication.
Project claim management is the central pillar of the overlapping areas of contract administration, contract law and building regulations. Delays caused by inefficiency of the procedures designed to ...avoid disputes emerge at the pre-project phase and continue during construction. The quantum of research addressing this issue is not immediately transferrable between jurisdictions, mainly due to local specificity of construction practices, contract and construction laws, as well as clients’ preferences. The primary aim of this study is to identify the underlying causes of disputes that have arisen in the NSW construction industry in the past two decades and to analyze the inter-relationships between the causes. To achieve this purpose, PLS-SEM quantitative models were utilized to study different factors influencing disputes. Through a detailed quantitative analysis of 230 cases, based on dispute frequencies, causes and effect analysis and the resultant loop cause diagrams, the dispute triggers, types, and root causes have been analyzed as the basis for developing a model to predict the future likelihood of disputes. Finally, 13 causes of disputes have been recognized as the main causal factors in the construction projects in NSW. This study also has shown that payment and reimbursement-related disputes are the most frequent in NSW construction, except for the last two years.
Given the high demand in South Korea, apartments, constituting 78% of residential projects, have witnessed substantial construction. This growth has coincided with an increase in defects appearing ...throughout the life cycle of construction projects, frequently becoming a central factor in the escalating disputes between general contractors and occupants. Some defects only surface during occupancy, underscoring the need to address and fulfill occupant requirements during the repairing, given their dissatisfaction can fuel such disputes. Post-occupancy evaluation (POE) offers valuable feedback yet is often subjective, influenced by the perspectives of companies and managers, potentially failing to capture user experiences accurately. The development of POE concerning the construction defect repair service has not been paid attention to, for newly constructed apartments. To overcome these challenges, this paper introduces a Latent Dirichlet Allocation (LDA)-based framework for identifying evaluation metrics, enabling the development of a POE process for construction defect repair services in newly constructed apartments. As a result, “repeated construction”, “rapid response”, “promised fulfillment”, “punctuality”, “defect processing”, and “services and finishing” are identified as key evaluation metrics. Besides enhancing the serviceability of construction defect repair services, the proposed methodology offers the means to continuously monitor occupant experiences and preferences across varying times and regions.
•A Latent Dirichlet Allocation (LDA)-based framework was developed for identifying evaluation metrics in defect services.•The Post-Occupancy Evaluation (POE) process technique was adopted for newly constructed apartments in Korea.•A case demonstration was conducted using 32,895 sets of feedback (claims for defect repairs) from occupants (2018 to 2021).•The results highlight key evaluation metrics, including “repeated construction”, “rapid response” and “promise fulfillment”.
With apartment buildings representing a rapidly growing share of the residential market in South Korea, the effect of construction defects throughout the life cycle of construction projects, and ...particularly during the occupancy stage, has emerged as a significant social issue that may ultimately lead to an increase in defect disputes between new occupants and general contractors. An important step toward mitigating the likelihood of these defect disputes is to identify and address the factors that give rise to occupant dissatisfaction during the defect repair process. However, a reliable method by which to identify these factors has yet to be developed. In this respect, the main objective of the research presented in this paper is to develop a method for identifying occupant dissatisfaction factors in the construction defect repair stage. The developed method comprises the following procedures: (i) text pre-processing, which involves data cleaning, normalization, tokenization, morphological analysis, and removal of stopwords; (ii) term frequency–inverse document frequency for keyword extraction; and (iii) semantic network analysis to recognize relationships between words. The method was implemented using a dataset of 12,874 comments in Korean text format obtained from apartment building occupants. Based on the processing and analysis of this dataset, the occupant dissatisfaction factors were found to be: (i) inaccurate and inadequate repair work (represented by such keywords as “Repair”, “Visit”, and “Accuracy”); (ii) failure to keep promises (e.g., “Fulfillment”, “Promise”, and “Change”); and (iii) unprofessional conduct on the part of representatives in the repair service center (e.g., “Response”, “Attitude”, and “Receipt”).
High-rise building fires can pose a significant threat to occupants and firefighters. The state-of-the-art technologies such as sensor-based Internet of Things (IoT), Building Information Modelling ...(BIM), Virtual Reality (VR) and Augmented Reality (AR) may offer great potential to improve building fire safety and rescue efficiency, primarily through ameliorating the level of situational awareness. This study proposes an innovative technology integrated framework for prototyping a proof-of-concept BIM, IoT and AR/VR system based upon the rationale of situational awareness. A pilot test based on a simulated fire scenario is conducted to evaluate the functionality of the framework. The outcomes reveal that the data generated by the system can be leveraged by the firefighting department to quickly locate the whereabouts of the indoor fires, and the VR gamification scenarios can expedite the development of situational awareness for the trainees. The limitations and future works are also discussed at the end of this paper.
•Integrating Building Information Modelling and Internet of Things can provide fire monitoring.•Virtual Reality based fire training can increase situational awareness.•Augmented Reality can facilitate indoor pathfinding efficiency.•Firefighters' efficiency can be improved through this framework.
Output-oriented resource control in the traditional planning methods is still prevalent in construction industry. It frequently causes unpredictable wastes leading to deterioration of the sequenced ...supply chains. On the other hand, the use of feed-forward control offers the opportunity for prevention by ensuring the high quality of necessary process resources. This paper, in turn, presents a dynamic control approach that highlights the effectiveness of feed-forward control on minimising process wastes. The field experiment in this paper presents the rebar supply and placement on an actual construction site. It aims to measure the responsiveness of pre-controlled resources to ever-changing process performance. Collected data during this field study provided the basic data for establishing statistical relationships between resource logistics quality and process performance. The research experiments found out two of the critical resource logistics: (1) Available number of workers; and (2) Distance between resource and final place. Finally the proactive control on these entities resulted in a dramatic reduction of process waste, leading to the improvement of productive work rate (31.0 to 53.3%). The main contribution of the research lies on the first-hand investigation from a very probable situation, which would benefit practical engineers and construction managers.
The objective of the study presented in this paper is to determine the characteristics of the scaffolding supply chain in a liquefied natural gas (LNG) infrastructure project. This research is ...significant as the outsourcing of scaffolding is integral to its use and productivity toward LNG infrastructure project completion. As such, this paper presents the research undertaken on the subcontracting of scaffold manufacturing, supplying and delivering. It focuses upon the organisations, management and control in scaffolding subcontracting. A comparative analysis of three organisations was carried out to reveal issues with current practice in manufacturing, supplying and delivering scaffold products for assembly onsite. Their management and control approaches are also compared and contrasted. It is found that, while the divided contract approach may help save costs, enhance market exposure and is ideal when choice of subcontractor is limited, its risks can impact upon the entire project and be difficult for the contractor to control. The limited background in scaffolding studies and importance of subcontracting within LNG infrastructure projects has made this research timely. This paper identifies issues in relation to quality assurance, warranties and rework, which have the potential to mitigate any cost benefits obtained from subcontracting practices within this supply chain.
How to improve localization accuracy is a big challenge for highly dynamic and sparse industrial scenarios with active RFID tags. Since antenna of active tag is anisotropic, its emitting signal ...propagates damply with transmission distance and emitting orientation. In this paper, we aim at modeling anisotropic signal attenuation of active RFID tags by analyzing measurement data in real environment. As the features of signal attenuation with transmission distance on different signal-emitting orientations are the same, two basic models are regressed using experimental data firstly: 1) directional signal-distribution models for both horizontal and vertical orientation in a certain distance; 2) an attenuation model of RF signal with transmitting distance along one direction. Afterwards, an Anisotropic Signal Attenuation Model of active RFID tag (ASAM) is deduced. Furthermore, a noise filtering model in a tag-grid environment is optimized for the spatial model ASAM. Finally, the experimental results in 400-square-meter experimental field show that the average standard deviation (STD) of the optimized model reduces by 50% when the STD is bigger than 4-dB, and the probability distribution is over 70% when the deviation is less than 2.
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