Most construction worker education and training environments apply traditional teaching methods to educate workers about hazards and productivity in the workplace. Many rely on using conventional ...teacher–student classroom settings, but there are few effective interactive methods applied which can objectively engage trainer and trainees and assess their performance during and after training sessions. Presented is a novel approach towards integrating real-time location tracking and three-dimensional immersive data visualization technologies in existing construction worker education and training environments. The scope is limited to steel-erection tasks performed by union ironworkers in an indoor training center. Results to analysis and visualization of the gathered data from training session are shown. The potential for assessing and improving the trainers' and apprentices' safety and productivity performance is explained. Since such technologies have hardly been used as part of existing construction education and training techniques, the opportunities including return on investment and user feedback were studied. The results show that unsafe practices in worker training environments can be detected and visualized and furthermore their training effectiveness can be indirectly measured.
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•Construction worker education and training can leverage more technology.•Technology is shown that tracks and visualizes the location of workers in real-time.•Algorithms were developed that allow safety and work sampling analysis.•The approach was tested in a worker training center under realistic conditions.•Objective data recording and information visualization are possible.
AbstractWhen constructing and updating the built environment, ensuring the safety of all parties involved is of utmost importance. Traditionally, safety has been measured and managed reactively, ...where actions are taken in response to adverse trends in injuries. Alternatively, safety-related practices can be measured during the construction phase to trigger positive responses before an injury occurs. Despite the potential benefits of such strategies, few have been identified in the literature and there has yet to be an organized effort to codify and investigate these methods. A mixed-methods research approach was used to (1) clearly identify and define elements of the safety management process that can be measured and monitored during the construction phase, (2) describe resource requirements for measurement, monitoring, and response, and (3) describe specific management actions required when any indicator fails to satisfy a desired value. To produce internally and externally valid and reliable results, data were triangulated from case studies, content analysis of award-winning projects, and focused discussions among construction safety experts. In total, over 50 proactive metrics were identified, 13 of which were selected as top priority by expert professionals. Use of these indicators has been connected to exceptional safety performance in industry-leading organizations. The implication of the findings is that very strong safety outcomes can be expected if contractors build upon a robust safety management foundation with the use of these methods of project safety control.
This paper presents a computer vision based algorithm for automated 2D detection of construction workers and equipment from site video streams. The state-of-the-art research proposes semi-automated ...detection methods for tracking of construction workers and equipment. Considering the number of active equipment and workers on jobsites and their frequency of appearance in a camera's field of view, application of semi-automated techniques can be time-consuming. To address this limitation, a new algorithm based on Histograms of Oriented Gradients and Colors (HOG+C) is proposed. Our proposed detector uses a single sliding window at multiple scales to identify the potential candidates for the location of equipment and workers in 2D. Each detection window is first divided into small spatial regions and then the gradient orientations and hue–saturation colors are locally histogrammed and concatenated to form the HOG+C descriptors. Tiling the sliding detection window with a dense and overlapping grid of formed descriptors and using a binary Support Vector Machine (SVM) classifier for each resource enables automated 2D detection of workers and equipment. A new comprehensive benchmark dataset containing over 8000 annotated video frames including equipment and workers from different construction projects is introduced. This dataset contains a large range of pose, scale, background, illumination, and occlusion variation. Our preliminary results on detection of standing workers, excavators and dump trucks with an average accuracy of 98.83%, 82.10%, and 84.88% respectively indicate the applicability of the proposed method for automated activity analysis of workers and equipment from single video cameras. Unlike other state-of-the-art algorithms in automated resource tracking, this method particularly detects idle resources and does not need manual or semi-automated initialization of the resource locations in 2D video frames. The experimental results and the perceived benefits of the proposed method are discussed in detail.
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► We present a computer vision based method for automated 2D resource tracking. ► A comprehensive dataset of excavators, trucks, and standing workers is presented. ► Accuracies for excavators, trucks, and standing workers are 82.10, 84.88, and 98.83%.
The extent of effectiveness of real-time communication within BIM environment is somehow restrained due to the limited sense of immersion into virtual environments. The objective of this paper ...highlights the need for a structured methodology of fully integrating Augmented Reality (AR) technology in BIM. Based on the generic review of BIM in construction, this paper forms the rationales for the onsite information system for construction site activities, and then formulates the methods of configuring BIM+AR prototypes. It is demonstrated that, extended to the site via the “hand” of AR, the BIM solution can address more real problems, such as low productivity in retrieving information, tendency of committing error in assembly, and low efficiency of communication and problem solving.
•We discuss and investigate how BIM can be extended to the site via AR.•We demonstrate how AR and BIM can improve the way the information is accessed.•Our systems improve the productivity in the concerned rationales.
With widespread increasing applications of mechanized tunneling in almost all ground conditions, prediction of tunnel boring machine (TBM) performance is required for time planning, cost control and ...choice of excavation method in order to make tunneling economical. Penetration rate is a principal measure of full-face TBM performance and is used to evaluate the feasibility of the machine and predict advance rate of excavation. This research aims at developing a regression model to predict penetration rate of TBM in hard rock conditions based on a new artificial intelligence (AI) algorithm namely support vector regression (SVR). For this purpose, the Queens Water Tunnel, in New York City, was selected as a case study to test the proposed model. In order to find out the optimum values of the parameters and prevent over-fitting, 80% of the total data were selected randomly for training set and the rest were kept for testing the model. According to the results, it can be said that the proposed model is a useful and reliable means to predict TBM penetration rate provided that a suitable dataset exists. From the prediction results of training and testing samples, the squared correlation coefficient (R2) between the observed and predicted values of the proposed model was obtained 0.99 and 0.95, respectively, which shows a high conformity between predicted and actual penetration rate.
•Penetration rate of TBM was predicted using SVR algorithm.•A real dataset pertaining to the Queens tunnel was used to test the proposed model.•Both rock engineering properties and machine characteristics were considered.•R2 between the observed and predicted values of penetration rate was obtained 0.95.
AbstractBecause of its large size (30,000 m2 in plan), the 17.85- to 25.89-m-deep foundation pit of the 492-m-high Shanghai World Finance Center building was excavated by the central-island ...technique, i.e., bottom-up construction of the central cylindrical shaft first and then top-down construction of the peripheral rectangular pit. As part of the comprehensive study on the characteristics of this large-scale foundation pit, this study mainly focuses on the behaviors of the peripheral pit via the following investigated items: (1) lateral wall deflections; (2) vertical wall movements; (3) lateral ground movements; (4) axial forces in the cast floor slabs and braced struts; (5) lateral earth pressures on both sides of retaining walls; (6) variation of pore pressures along depth and deep artesian water levels; (7) ground settlements; (8) subsurface settlements; (9) basal heaves; (10) vertical column movements; and (11) column stresses. To explore the potential effects of pit sizes on the excavation behaviors, field data from another 33 top-down excavations in Shanghai were also included for comparison. The comprehensive comparisons show that in addition to the well-known factors (e.g., excavation depths, supporting system stiffness, and factor of safety against basal heave), pit sizes in plan played a key role in determination of the pit behaviors. The large-scale pits with the areas in plan of 30,000–50,000 m2 experienced wall deflections and ground settlements three to five times those of regular building basement and metro station excavations with the sizes in plan no more than 6,000 m2, and the corresponding influence zones behind the large-sized pits were also much wider. Different from the braced struts that just carried the load because of soil removal in the proximity, the floor slabs sustained the load induced by exposure of the entire retaining wall along the depth. For the top-down excavations in Shanghai soft clay, the lateral earth pressure envelopes behind the retaining walls were trapezoidal, but their magnitudes were significantly smaller than those predicted by the methods available in the literature, and the corresponding peak values occurred at a greater depth. The influence zones of basal heave caused by soil removal (stress relief) extended much deeper below the excavation bases than those assumed in the conventional slip circle basal stability models.
This study aims to explore the less explored area of leadership behaviors within public construction project organizations. A correlational research design was adopted, with data collected through a ...questionnaire-based survey of 169 professionals involved in public construction projects in Vietnam. Structural equation modeling with partial least squares estimation was used to analyze the data. The results confirmed five behavioral dimensions, namely motivating leadership, goal setting, supportive leadership, participative leadership, and directive leadership, which can be used to assess the leading function in public construction work management. The study also revealed that supportive leadership and directive leadership have a significant impact on management effectiveness. Additionally, supportive leadership acts as a mediator for goal setting, motivating leadership, and participative leadership, while directive leadership acts as a mediator for goal setting and participative leadership.
Abstract
Quartz, asbestos and chromium (VI) compounds can be found again and again in tunnel construction, especially quartz dust is an everyday companion at tunnel construction sites in Austria. The ...dusts from quartz, asbestos and chromium (VI) compounds are clearly carcinogenic, so measures to avoid and minimize dust exposure for employees are accordingly important. In the 2021 limit value ordinance, the limit value for fine quartz dust was reduced to 0.05 mg / m
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, i.e. to a third of the previous value. Reaching this limit value represents a new challenge for everyone involved in underground projects, and the new RVS 09.01.53 is meant to provide a guideline for the planning of appropriate protective measures. The RVS 09.01.53 is expected to be published in autumn 2021.
Abstract
Quarz, Asbest und Chrom(VI)‐Verbindungen sind im Tunnelbau immer wieder anzutreffen, insbesondere Quarzstaub ist in Österreich alltäglicher Begleiter im Tunnel. Die Stäube von Quarz, Asbest und Chrom(VI)‐Verbindungen gelten als eindeutig krebserzeugend, entsprechend wichtig sind Maßnahmen zur Vermeidung und Minimierung der Staubbelastung für die Arbeitnehmer. In der Grenzwerteverordnung 2021 wurde der Grenzwert für Quarzfeinstaub auf 0,05 mg/m
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herabgesetzt, d. h. auf ein Drittel des davor gültigen Werts. Das Erreichen dieses Grenzwerts stellt für alle an Untertageprojekten Beteiligten eine neue Herausforderung dar, zu deren Bewältigung die neue RVS 09.01.53 eine Hilfestellung und eine Anleitung zur Planung von Schutzmaßnahmen bieten soll. Die RVS 09.01.53 wird voraussichtlich im Herbst 2021 veröffentlicht.
Abstract
Cooperation on the construction site means less stress, a better atmosphere, working together to find solutions and fun at work. This gives the opportunity to focus more on the technical ...challenges, because much less time is needed to settle disputes. This also requires significantly less administrative cost and thus ensures greater efficiency, because any improvement in communication creates trust and openness, reduces controversial correspondence and the risk of misunderstandings. The working group ”Cooperative Project Management“ of the ÖBV, launched a pilot project in 2016 to measure the cooperation on construction sites. Ongoing anonymous surveys of key people in a construction project were intended to establish mutual cooperation and, in particular, to monitor its development over time. On the basis of these findings, it should be possible to detect and counteract any undesirable developments in cooperation on construction projects at an early stage.
Abstract
Kooperation auf der Baustelle bedeutet weniger Stress, ein besseres Arbeitsklima, gemeinsame Lösungsorientierung und Spaß an der Arbeit. Damit besteht die Möglichkeit, sich besser auf die technischen Herausforderungen zu konzentrieren, weil wesentlich weniger Zeit zum Streitschlichten benötigt wird. Das erfordert auch deutlich weniger Administrationsaufwand und sorgt dadurch für mehr Effizienz, denn jede Verbesserung der Kommunikation schafft Vertrauen und Offenheit, reduziert kontroversiellen Schriftverkehr und die Gefahr von Missverständnissen. Im Rahmen des Arbeitskreises „Kooperative Projektabwicklung” der ÖBV wurde im Jahr 2016 ein Pilotprojekt gestartet, um die Kooperation auf der Baustelle zu messen. Durch laufende anonyme Befragungen der Schlüsselpersonen in einem Bauprojekt sollte die wechselseitige Kooperation erhoben und insbesondere deren zeitliche Entwicklung verfolgt werden. Aufgrund dieser Erkenntnisse sollte in Bauprojekten die Möglichkeit geschaffen werden, frühzeitig Fehlentwicklungen bei der Kooperation zu erkennen und entsprechend gegenzusteuern.
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