Habibnezhad, M.; Puckett, J.; Fardhosseini, M.S.; Pratama, L.A. (2019). A Mixed VR and Physical Framework to Evaluate Impacts of Virtual Legs and Elevated Narrow Working Space on Construction Workers Gait Pattern. Arxiv, 7 pp.
View Publication
Abstract
It is difficult to conduct training and evaluate workers' postural performance by using the actual job site environment due to safety concerns. Virtual reality (VR) provides an alternative to create immersive working environments without significant safety concerns. Working on elevated surfaces is a dangerous scenario, which may lead to gait and postural instability and, consequently, a serious fall. Previous studies showed that VR is a promising tool for measuring the impact of height on the postural sway. However, most of these studies used the treadmill as the walking locomotion apparatus in a virtual environment (VE). This paper was focused on natural walking locomotion to reduce the inherent postural perturbations of VR devices. To investigate the impact of virtual height on gait characteristics and keep the level of realism and feeling of presence at their highest, we enhanced the first-person-character model with "virtual legs". Afterward, we investigated its effect on the gait parameters of the participants with and without the presence of height. To that end, twelve healthy adults were asked to walk on a virtual loop path once at the ground level and once at the 17th floor of an unfinished structure. By quantitatively comparing the participants' gait pattern results, we observed a decrease in the stride length and increase in the gait duration of the participants exposed to height. At the ground level, the use of the enhanced model reduced participants' average stride length and height. The results of this study help us understand users' behaviors when they were exposed to elevated surfaces and establish a firm ground for gait stability analysis for the future height-related VR studies. We expect this developed VR platform can generate reliable results of VR application in more construction safety studies.
Keywords
Civil Engineering Computing; Construction Industry; Gait Analysis; Medical Computing; Occupational Safety; Virtual Reality; Construction Safety Studies; Mixed Vr; Virtual Legs; Construction Workers Gait Pattern; Immersive Working Environments; Postural Instability; Serious Fall; Postural Sway; Walking Locomotion Apparatus; Natural Walking Locomotion; Inherent Postural Perturbations; Vr Devices; Virtual Height; First-person-character Model; Gait Parameters; Virtual Loop Path; Stride Length; Gait Duration; Gait Stability Analysis; Safety Concerns; Vr Platform; Height-related Vr Studies
Adhikari, Pramodit; Mahmoud, Hussam; Xie, Aiwen; Simonen, Kathrina; Ellingwood, Bruce. (2020). Life-Cycle Cost and Carbon Footprint Analysis for Light-framed Residential Buildings Subjected to Tornado Hazard. Journal Of Building Engineering, 32.
View Publication
Abstract
Light-frame wood building construction dominates the single-family residential home market in the United States. Such buildings are susceptible to damage from extreme winds due to hurricanes in coastal areas and tornados in the Midwest. The consequences of extreme winds on the built environment and on social and economic institutions within the community can be severe and are likely to increase in the coming decades as a result of increases in urbanization and economic development and the potential impacts of changing climate in hazard prone areas. Current building practices provide minimum standards for occupant safety and health, including structural integrity, water and sanitation, lighting, ventilation, means of egress and fire protection. However, they generally do not consider building resilience, which includes robustness and an ability to recover following extreme natural hazard events. Nor do they address sustainability, the notion that building design, construction and rehabilitation should not adversely impact the environment. In this paper, we establish a generalized cost and carbon footprint life-cycle analysis methodology for examining the benefits of different building practices for residential light-frame wood construction subjected to tornado hazards. A multiobjective approach is used to reveal tradeoffs between resilient and sustainable practices for typical residential construction. We show that when the life cycle of a typical residence is considered, a balance between resilience, sustainability and cost might be achieved in design and rehabilitation of residential building construction for tornado hazards.
Keywords
Performance; Risk; Fragility; Residential Buildings; Life-cycle Analysis; Resilience; Optimal Decisions; Sustainable Construction; Tornadoes
Nnaji, Chukwuma; Karakhan, Ali A.; Gambatese, John; Lee, Hyun Woo. (2020). Case Study to Evaluate Work-Zone Safety Technologies in Highway Construction. Practice Periodical On Structural Design And Construction, 25(3).
View Publication
Abstract
The construction industry is known for its conservative approach toward adopting new, emerging technologies. This conservative approach for adopting technology is caused by multiple factors including the lack of adequate resources to guide construction practitioners in the process of evaluating whether a construction firm should adopt a certain technology or not. Previous studies have already proposed rigorous protocols for evaluating work-zone technologies, but the implementation of such protocols is still unclear to many construction practitioners. The objective of this study is to provide a case study example of how evaluation protocols can be used in practice to determine whether a firm should adopt a certain work-zone technology. The case study focused on assessing the usefulness of commercially available work-zone intrusion alert technologies (WZIATs). The results of the evaluation revealed that some WZIATs could be more attractive to construction organizations and agencies in terms of providing louder alarms, being more mobile, and allowing a higher transmission range. The case study example discussed in this study is expected to provide invaluable practical information to practitioners in the construction industry interested in evaluating and adopting emerging technologies.
Keywords
Construction Industry; Mobile Radio; Occupational Safety; Road Building; Road Safety; Highway Construction; Conservative Approach; Construction Practitioners; Construction Firm; Rigorous Protocols; Work-zone Technology; Case Study Example; Evaluation Protocols; Commercially Available Work-zone Intrusion Alert Technologies; Construction Organizations; Evaluate Work-zone Safety Technologies; Speed; Signs; Work Zone; Safety Technology; Intrusion Alert; Evaluation Protocol
Shtrepi, Louena; Echenagucia, Tomás Méndez; Badino, Elena; Astolfi, Arianna. (2021). A Performance-based Optimization Approach For Diffusive Surface Topology Design. Building Acoustics, 28(3), 231 – 247.
View Publication
Abstract
Different numerical techniques have been used in the last decades for the acoustic characterization and performance optimization of sound diffusive surfaces. However, these methods require very long calculation times and do not provide a rapid feedback. As a result, these methods can hardly be applied by designers at early stages of the design process, when successive design iterations are necessary from an aesthetic point of view. A suitable alternative could be the use of parametric modeling in combination with performance investigations during the design process of sound diffusive surfaces. To this aim, this study presents a design process for diffusive surfaces topology optimization based on the combination of parametric models and geometrical acoustic simulations. It aims to provide architects and designers with rapid visual feedback on acoustic performances at a preliminary stage of the design process. The method has been tested on different case studies, which have been modelled based on geometric guidelines for diffusive surface optimization. The sensitivity of the method showed that it could be a very useful tool for comparisons among surface design alternatives. Finally, the advantages and limitations of the integrated optimization in comparison with conventional optimizations are discussed.
Keywords
Acoustic Performance; Room Acoustics; Scattering; Coefficients; Accuracy; Field; Simulations; Diffusion; Surface Optimization; Performance-based Design
Neff, Gina; Fiore-Silfvast, Brittany; Dossick, Carrie Sturts. (2010). A Case Study of the Failure of Digital Communication to Cross Knowledge Boundaries in Virtual Construction. Information Communication & Society, 13(4), 556 – 573.
View Publication
Abstract
When can digital artefacts serve to bridge knowledge barriers across epistemic communities? There have been many studies of the roles new information and communication technologies play within organizations. In our study, we compare digital and non-digital methods of inter-organizational collaboration. Based on ethnographic fieldwork on three construction projects and interviews with 65 architects, engineers, and builders across the USA, we find that IT tools designed to increase collaboration in this setting instead solidify and make explicit organizational and cultural differences between project participants. Our study suggests that deeply embedded disciplinary thinking is not easily overcome by digital representations of knowledge and that collaboration may be hindered through the exposure of previously implicit distinctions among the team members' skills and organizational status. The tool that we study, building information modelling, reflects and amplifies disciplinary representations of the building by architects, engineers, and builders instead of supporting increased collaboration among them. We argue that people sometimes have a difficult time overcoming the lack of interpretive flexibility in digital coordinating tools, even when those tools are built to encourage interdisciplinary collaboration.
Keywords
Digital Communications; Data Transmission Systems; Communication & Technology; Digital Electronics; System Analysis; Building Information Modelling; Collaboration; Qualitative Methods; Teams; Civil Engineering Computing; Digital Communication; Groupware; Knowledge Representation; Organisational Aspects; Virtual Reality; Case Study; Virtual Construction; Knowledge Barriers; Epistemic Community; Interorganizational Collaboration; Ethnographic Fieldwork; Interpretive Flexibility; Digital Coordinating Tool; Digital Collaboration; Technology; Objects; Design; Representations; Organizations
Cheng, Tao; Teizer, Jochen; Migliaccio, Giovanni C.; Gatti, Umberto C. (2013). Automated Task-Level Activity Analysis through Fusion of Real Time Location Sensors and Worker’s Thoracic Posture Data. Automation In Construction, 29, 24 – 39.
View Publication
Abstract
Knowledge of workforce productivity and activity is crucial for determining whether a construction project can be accomplished on time and within budget. Significant work has been done on improving and assessing productivity and activity at task, project, or industry levels. Task level productivity and activity analysis are used extensively within the construction industry for various purposes, including cost estimating, claim evaluation, and day-to-day project management. The assessment is mostly performed through visual observations and after-the-fact analyses even though previous studies show automatic translation of operations data into productivity information and provide spatial information of resources for specific construction operations. An original approach is presented that automatically assesses labor activity. Using data fusion of spatio-temporal and workers' thoracic posture data, a framework was developed for identifying and understanding the worker's activity type over time. This information is used to perform automatic work sampling that is expected to facilitate real-time productivity assessment. Published by Elsevier B.V.
Keywords
Detectors; Construction Projects; Labor Supply; Real-time Control; Construction Costs; Project Management; Machine Translating; Activity And Task Analysis; Construction Worker; Data Fusion; Health; Location Tracking; Productivity; Safety; Sensors; Thoracic Posture Data; Workforce; Construction Industry; Costing; Labour Resources; Sensor Fusion; Real-time Productivity Assessment; Automatic Work Sampling; Worker Activity Type; Spatio-temporal Data; Labor Activity Assessment; Construction Operations; Spatial Information; Productivity Information; Day-to-day Project Management; Claim Evaluation; Cost Estimating; Task Level Productivity; Industry Levels; Project Levels; Construction Project; Workforce Activity; Workforce Productivity; Worker Thoracic Posture Data; Real Time Location Sensors Fusion; Automated Task-level Activity Analysis; Construction-industry Productivity
Gatti, Umberto C.; Migliaccio, Giovanni C.; Bogus, Susan M.; Schneider, Suzanne(3). (2014). An Exploratory Study of the Relationship between Construction Workforce Physical Strain and Task Level Productivity. Construction Management And Economics, 32(6), 548 – 564.
View Publication
Abstract
The monitoring of construction workforce physical strain can be a valuable management strategy in improving workforce productivity, safety, health, and quality of work. Nevertheless, clear relationships between workforce performance and physical strain have yet to be established. An exploratory investigation of the relationship between task level productivity and physical strain was conducted. Nine participants individually performed a four-hour simulated construction task while a wearable physiological status monitor continuously assessed their physiological condition. Heart rate, relative heart rate, and breathing rate were utilized as predictors of physical strain, and task level-single factor productivity was used as an index of productivity. Numerous regression models were generated using the collected data. This investigation initially unsuccessfully attempted to establish a relationship between physiological condition and productivity at the individual worker level. However, an analysis of the regression models showed that there is a relationship between productivity and either heart rate or relative heart rate at the group level, and that this relationship is parabolic. Breathing rate was proved to not be a significant predictor of productivity. Research results significantly improve understanding of the relationship between work physiology and task productivity. Researchers and practitioners may use the tested monitoring devices, analysis methods, and results to design further applied studies and to improve workforce productivity. © 2013 © 2013 Taylor & Francis.
Keywords
Heart; Industrial Hygiene; Occupational Risks; Personnel; Regression Analysis; Construction Workforces; Management Strategies; Occupational Health And Safety; Operations Management; Physiological Condition; Physiological Status Monitors; Work Physiology; Workforce
Migliaccio, G. C.; Zandbergen, Paul; Martinez, A. A. (2015). Empirical Comparison of Methods for Estimating Location Cost Adjustments Factors. Journal Of Management In Engineering, 31(2).
View Publication
Abstract
Location factors are used to adjust conceptual cost estimates by project location. Presently, the construction industry has adopted a simple, proximity-based interpolation method to estimate location factors for missing locations. Although this approach is widely accepted, its validity has not been statistically substantiated. This study assessed the current method of adjusting conceptual cost estimates by project location and compared its performance against two alternative spatial interpolation methods. A Moran's I test was used to confirm the presence of strong spatial autocorrelation, which supports the use of proximity-based methods. Additional statistical evaluations of current and alternative methods were also conducted. Results provided statistical justification for the current method. However, an alternative method was proven to outperform the current method. Moreover, several opportunities for future research were identified as a result of this exploratory study. (C) 2014 American Society of Civil Engineers.
Keywords
Construction Industry; Interpolation; Statistical Analysis; Location Cost Adjustment Factor; Proximity-based Interpolation Method; Project Location; Spatial Interpolation Method; Moran I Test; Spatial Autocorrelation; Statistical Evaluation; Geographical Information-systems; Construction; Layout; Gis; Conceptual Estimating; Geographic Information Systems; Construction Costs; Planning; Location Adjustments
Kim, Taehoon; Kim, Yong-woo; Cho, Hunhee. (2016). Customer Earned Value: Performance Indicator from Flow and Value Generation View. Journal Of Management In Engineering, 32(1).
View Publication
Abstract
The earned value method (EVM) is considered an advanced project control technique that provides a quantitative measure of work performance. However, the EVM is effective only under the assumption that every activity is independent. Literature shows that the EVM lacks the value generation view even working against the reliability of workflow. The goal of this research is to propose a project metric system to supplement the EVM in terms of the workflow and value generation. The researchers suggest a new metric of customer earned value (CEV), which is defined as the budgeted amount of work completed and is used by the successors on a network. Through a hypothetical case study, this research investigates how the work-in-process between trades and schedule performance in each trade behave under different uncertainties. The result suggests that the proposed metrics can provide project managers with more relevant managerial information on project progress as well as on the level of collaboration. The proposed system with the EVM would facilitate collaboration on project planning and control where variability and interdependency are involved. (C) 2015 American Society of Civil Engineers.
Keywords
Budgeting; Customer Services; Organisational Aspects; Planning; Project Management; Customer Earned Value; Project Planning; Project Managers; Trade-schedule Performance; Work-in-process; Budgeted Amount; Project Metric System; Advanced Project Control Technique; Earned Value Method; Performance Indicator; Value Generation View; Management; Project Control Metric; Collaboration
Lee, Wonil; Seto, Edmund; Lin, Ken-yu; Migliaccio, Giovanni C. (2017). An Evaluation Of Wearable Sensors And Their Placements For Analyzing Construction Worker’s Trunk Posture In Laboratory Conditions. Applied Ergonomics, 65, 424 – 436.
View Publication
Abstract
This study investigates the effect of sensor placement on the analysis of trunk posture for construction activities using two off-the-shelf systems. Experiments were performed using a single-parameter monitoring wearable sensor (SPMWS), the ActiGraph GT9X Link, which was worn at six locations on the body, and a multi-parameter monitoring wearable sensor (MPMWS), the Zephyr BioHarnessTM3, which was worn at two body positions. One healthy male was recruited and conducted 10 experiment sessions to repeat measurements of trunk posture within our study. Measurements of upper-body thoracic bending posture during the lifting and lowering of raised deck materials in a laboratory setting were compared against video-captured observations of posture. The measurements from the two sensors were found to be in agreement during slow-motion symmetric bending activities with a target bending of <= 45. However, for asymmetric bending tasks, when the SPMWS was placed on the chest, its readings were substantially different from those of the MPMWS worn on the chest or under the armpit. (C) 2017 Elsevier Ltd. All rights reserved.
Keywords
Detectors; Construction Workers; Posture; Wearable Technology; Accelerometers; Work-related Injuries; Health; Accelerometer For Inclinometry; Construction Worker; Work-related Musculoskeletal Disorder; Motion Measurement; Position Measurement; Sensor Placement; Upper-body Thoracic Bending Posture Measurements; Trunk Posture Measurements; Zephyr Bioharness 3; Sensor Placement Effect; Construction Worker Trunk Posture Analysis; Wearable Sensor Evaluation; Asymmetric Bending Tasks; Slow-motion Symmetric Bending Activities; Mpmws; Multiparameter Monitoring Wearable Sensor; Actigraph Gt9x Link; Spmws; Single-parameter Monitoring Wearable Sensor; Low-back-pain; Physical-activity Assessment; Risk-factors; Musculoskeletal Disorders; Reliability; Movements; Validity; System; Gt3x+accelerometer