Lee, Wonil; Migliaccio, Giovanni Ciro. (2016). Physiological Cost Of Concrete Construction Activities. Construction Innovation, 16(3), 281 – 306.
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Abstract
Purpose - The purpose of this paper was to investigate the physiological cost of concrete construction activities. Design/methodology/approach - Five concrete construction workers were recruited. The workers' three-week heart rate (HR) data were collected in summer and autumn. In this paper, several HR indexes were used to investigate the physiological cost of work in concrete construction trades, including average working HR, relative HR and ratio of working HR to resting HR. Findings - This paper measures how absolute and relative HRs vary throughout a workday and how working HR compares to resting HR for individual workers. Research limitations/implications - Field observations are usually extremely difficult as researchers need to overcome a number of barriers, including employers' resistance to perceived additional liabilities, employees' fear that their level of activity will be reported to managers and many other practical and technical difficulties. As these challenges increase exponentially with the number of employers, subjects and sites, this study was limited to a small number of subjects all working for the same employer on the same jobsite. Still, challenges are often unpredictable and lessons learned from this study are expected to guide both our and other researchers' continuation of this work. Originality/value - The time effect on the physiological cost of work has not been considered in previous studies. Thus, this study is noteworthy owing to the depth of the data collected rather than the breadth of the data.
Keywords
Concrete; Construction Industry; Costing; Human Resource Management; Occupational Health; Personnel; Physiology; Physiological Cost; Concrete Construction Activity; Construction Workers; Summer; Autumn; Construction Trade; Working Heart Rate; Relative Heart Rate; Resting Heart Rate; Employee Fear; Jobsite; Heart-rate Strain; Stress; Work; Risk; Management; Fusion; Model; Index; Biosensing And Environmental Sensing; Occupational Safety And Health; Threshold Limit Value; Work Physiology
Kim, Jonghyeob; Lee, Hyun Woo; Bender, William; Hyun, Chang-taek. (2018). Model for Collecting Replacement Cycles of Building Components: Hybrid Approach of Indirect and Direct Estimations. Journal Of Computing In Civil Engineering, 32(6).
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Abstract
Building maintenance, repair, and replacement (MR&R) costs are estimated to be two to three times larger than initial construction costs. Thus, it is important to accurately estimate and manage MR&R costs in the planning phase and/or design phase of a construction project based on life cycle cost analysis (LCCA). However, the nature of LCCA requires making necessary assumptions for the prediction and analysis of MR&R costs, and the reliability of the assumptions greatly impacts LCCA results. In particular, determining reasonable replacement cycles is especially important given that each replacement typically involves a significant amount of capital. However, conventional approaches largely focus on either collecting component-specific replacement cases or surveying expert opinions, both of which reduce the usability and reliability of replacement cycle data at an early stage. To overcome these limitations, this study aims to develop a replacement cycle collection model that can expedite the data collection by combining indirect estimations with direct estimations. The development of the model involves collecting replacement cases, developing replacement cycle and index estimation methods, and developing an algorithm to implement the suggested model. As a validation, the applicability and effectiveness of the model were illustrated and tested by using simulated cases based on 21 real-world facilities. This study makes a theoretical contribution to the body of knowledge by developing a replacement cycle data collection model based on long-term and macro perspectives. The developed model will also be of value to practitioners when they try to improve the reliability of their LCCA.
Keywords
Buildings (structures); Life Cycle Costing; Maintenance Engineering; Structural Engineering; Building Components; Building Maintenance; Planning Phase; Design Phase; Construction Project; Life Cycle Cost Analysis; Replacement Cycle Data Collection Model; Construction Costs; Lcca; Maintenance Repair And Replacement Cost; Service Life Prediction; Repair; Replacement; Replacement Cycles; Replacement Index; Database; Indirect Estimations
Gomez-Cunya, Luis-Angel; Fardhosseini, Mohammad Sadra; Lee, Hyun Woo; Choi, Kunhee. (2020). Analyzing Investments in Flood Protection Structures: A Real Options Approach. International Journal Of Disaster Risk Reduction, 43.
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Abstract
The soaring number of natural hazards in recent years due largely to climate change has resulted in an even higher level of investment in flood protection structures. However, such investments tend to be made in the aftermath of disasters. Very little is known about the proactive planning of flood protection investments that account for uncertainties associated with flooding events. Understanding the uncertainties such as when to invest on these structures to achieve the most optimal cost-saving amount is outmost important. This study fills this large knowledge gap by developing an investment decision-making assessment framework that determines an optimal timing of flood protection investment options. It combines real options with a net present value analysis to examine managerial flexibility in various investment timing options. Historical data that contain information about river water discharges were leveraged as a random variable in the modeling framework because it may help investors better understand the probability of extreme events, and particularly, flooding uncertainties. A lattice model was then used to investigate potential alternatives of investment timing and to evaluate the benefits of delaying investments in each case. The efficacy of the proposed framework was demonstrated by an illustrative example of flood protection investment. The framework will be used to help better inform decision makers.
Keywords
Decision-making; Flood Protection; Real Options Theory; Investment Decision-making
Homayouni, Hoda; Dossick, Carrie Sturts; Neff, Gina. (2021). Three Pathways to Highly Energy Efficient Buildings: Assessing Combinations of Teaming and Technology. Journal Of Management In Engineering, 37(2).
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Abstract
Highly energy efficient (HEE) buildings require a whole-system approach to building design. Scholars have suggested many tools, techniques, and processes to address the cross-disciplinary complexities of such an approach, but how these elements might be best combined to lead to better project outcomes is yet unknown. To address this, we surveyed architects associated with 33 AIA-COTE award-winning projects on the social, organizational, and technological elements of whole-system design (WSD) practices. We then used fuzzy sets-qualitative comparative analysis (fsQCA) to analyze the interdependencies among those elements. We found three distinct pathways for the design and construction of HEE buildings: information-driven, process-driven, or organization-driven. We also found that HEE buildings share some conditions for success, including having shared goals, owners engagement in the design process, and frequent and participatory interorganizational meetings. Our findings can help practitioners strategize and make decisions on incorporating WSD elements associated with their project types. Moreover, these results provide a launchpad for scholars to investigate complementarities among elements facilitating the design and construction process of HEE projects.
Keywords
Buildings (structures); Construction; Design Engineering; Energy Conservation; Fuzzy Set Theory; Innovation Management; Organisational Aspects; Project Management; Team Working; Whole-system Approach; Building Design; Cross-disciplinary Complexities; Social Elements; Organizational Elements; Technological Elements; Whole-system Design Practices; Fuzzy Set; Distinct Pathways; Hee Buildings; Project Types; Construction Process; Hee Projects; Highly Energy Efficient Buildings; Whole-system Design; Energy Efficient Buildings; Building Information Modeling; Integrated Project Teams; Fuzzy Sets-qualitative Comparative Analysis
Cheng, Tao; Migliaccio, Giovanni C.; Teizer, Jochen; Gatti, Umberto C. (2013). Data Fusion of Real-Time Location Sensing and Physiological Status Monitoring for Ergonomics Analysis of Construction Workers. Journal Of Computing In Civil Engineering, 27(3), 320 – 335.
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Abstract
Previous research and applications in construction resource optimization have focused on tracking the location of material and equipment. There is a lack of studies on remote monitoring for improving safety and health of the construction workforce. This paper presents a new approach for monitoring ergonomically safe and unsafe behavior of construction workers. The study relies on a methodology that utilizes fusion of data from continuous remote monitoring of construction workers' location and physiological status. To monitor construction workers activities, the authors deployed nonintrusive real-time worker location sensing (RTLS) and physiological status monitoring (PSM) technology. This paper presents the background and need for a data fusion approach, the framework, the test bed environment, and results to some case studies that were used to automatically identify unhealthy work behavior. Results of this study suggest a new approach for automating remote monitoring of construction workers safety performance by fusing data on their location and physical strain. DOI: 10.1061/(ASCE)CP.1943-5487.0000222. (C) 2013 American Society of Civil Engineers.
Keywords
Civil Engineering Computing; Construction Industry; Ergonomics; Occupational Health; Occupational Safety; Personnel; Sensor Fusion; Psm Technology; Rtls Technology; Construction Workforce Health; Construction Workforce Safety; Equipment Location; Material Location; Construction Resource Optimization; Construction Worker; Ergonomics Analysis; Physiological Status Monitoring; Realtime Location Sensing; Data Fusion; Exposure; Tracking; Demands; Sensors; System; Construction Worker Behavior; Remote Location Sensing; Work Sampling; Workforce Safety And Health
Gatti, U.C.; Migliaccio, G.C.; Laird, L. (2014). Design Management in Design-Build Megaprojects: SR 99 Bored Tunnel Case Study. Practice Periodical On Structural Design And Construction, 19(1), 148-58.
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Abstract
The increasing use of the design-build project delivery method has resulted in it now being one of the most popular nontraditional methods for delivering road, bridge, mass transit, and rail projects in the United States. However, although the use of design-build is widespread, there remains a substantial lack of information about how to effectively plan and implement design management procedures for design-build transportation projects. In particular, transportation agencies lack information about how to shape appropriate design management roles for various contractual parties and to manage design activities for design-build megaprojects. To fill this gap, this paper presents a case study of the SR 99 Bored Tunnel project in Seattle, Washington. It provides detailed information on how the owner, the Washington State DOT (WSDOT), incorporated design management procedures into its requirements and how the design-builder, Seattle Tunnel Partners, implemented them within its project management processes.
Keywords
Boring; Design Engineering; Project Management; Tunnels; Design-build Megaproject; Design-build Project Delivery Method; Road Project; Bridge Project; Mass Transit Project; Rail Project; United States; Design-build Transportation Project; Transportation Agency; Sr 99 Bored Tunnel Project; Seattle; Washington State Dot; Wsdot; Design Management; Project Management Process
Shakouri, Mahmoud; Lee, Hyun Woo; Choi, Kunhee. (2015). PACPIM: New Decision-Support Model of Optimized Portfolio Analysis for Community-Based Photovoltaic Investment. Applied Energy, 156, 607 – 617.
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Abstract
Inherent in large-scale photovoltaic (PV) investments is volatility that stems from a unique set of spatial factors, such as shading, building orientation, and roof slope, which can significantly affect both the level of risk and the return on investment. In order to systematically assess and manage the volatility, this study seeks to create a quantitative decision-support model: Portfolio Analysis for Community-based PV Investment Model (PACPIM). Focusing on residential PV systems, PACPIM determines optimized portfolios by applying the Mean Variance Portfolio theory. The model is intended to play an instrumental role in: (1) maximizing the hourly electricity output of PV systems; (2) minimizing the hourly volatility in electricity output; and (3) optimizing the risk-adjusted performance of community-based PV investment. The application and framework of PACPIM were deployed with an actual residential community consisting of 24 houses and their simulated data utilizing PVWatts (R) for estimating hourly electricity production. Results reveal that the optimized portfolios developed by PACPIM (1) increased annual electricity output of PV systems by 4.6%; (2) reduced the volatility in electricity output by 4.3%; and (3) offered the highest risk-adjusted performance among all possible portfolios based on the Sharpe ratios. This study is expected to effectively assist project owners and investors in systematically assessing their community-based PV projects and in developing optimized investment strategies. (C) 2015 Elsevier Ltd. All rights reserved.
Keywords
Photovoltaic Cells; Rate Of Return; Electricity; Dwellings; Electric Utilities; Community-based Investments; Decision-support Model; Mean–variance Portfolio Theory; Residential Photovoltaic Systems; Solar Energy; Decision Support Systems; Investment; Photovoltaic Power Systems; Large-scale Photovoltaic Investments; Spatial Factors; Shading; Building Orientation; Roof Slope; Return On Investment; Quantitative Decision-support Model; Portfolio Analysis For Community-based Pv Investment Model; Pacpim; Residential Pv Systems; Mean-variance Portfolio Theory; Hourly Electricity Output; Hourly Volatility; Risk-adjusted Performance; Hourly Electricity Production Estimation; Community-based Pv Projects; Optimized Investment Strategies; Romanian National Strategy; Renewable Energy; Public-attitudes; Wind Power; Pv Module; Performance; Implementation; Efficiency; Form; Economic Theory; Electricity Generation; Models; Risk; Shade; Solar Collectors
Ottesen, Jeffery L.; Migliaccio, Giovanni C.; Wulfsberg, H. James. (2016). Contractual Battles for Higher Ground: Case Examples. Journal Of Legal Affairs And Dispute Resolution In Engineering And Construction, 8(1).
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Abstract
Dispute resolution requires pursuit of mutual agreement and implies accordant resolve between the disputing parties. In truth, mutual agreement stems from acceptable risks and negotiated terms centered upon equity arguments wherein the parties assess, evaluate, negotiate, and battle for high ground. Where the parties clearly understand their respective positions relative to the applicable laws, facts outweigh emotions, and the parties are more likely to avoid disputes. This paper defines high ground based upon legal theory in quantum meruit, which means, as much as he deserves. Equity arguments can trump written contractual provisions. Owners, architects, engineers, and contractors must become wise to these arguments to protect its shareholders' interests. To promote understanding, five different case scenarios are presented using actual disputes experienced on (1) notice provisions, (2) cumulative impact claims, (3) no damages for delay clauses, (4) acceleration, and (5) owner review durations. These case scenarios demonstrate that acquiring high ground requires clear understanding and synchronization of both the contract and the applicable governing laws. Ultimately, the party possessing higher ground will find itself in a more favorable position when disputes occur. (c) 2015 American Society of Civil Engineers.
Keywords
Legislation; Subcontracting; Disputing Parties; Equity Arguments; Legal Theory; Quantum Meruit; Contractual Provisions; Architects; Notice Provisions; Cumulative Impact Claims; Owner Review Durations; Governing Laws; Engineers; Contractors; Dispute Resolution; Contractual Battles; Project; Equity; Delay; Contractual Notice; Cumulative Impact; Total Cost Claim; No Damages For Delay; Acceleration
Lee, Hyun Woo; Harapanahalli, Bharat Anand; Nnaji, Chukwuma; Kim, Jonghyeob; Gambatese, John. (2018). Feasibility of Using QR Codes in Highway Construction Document Management. Transportation Research Record, 2672(26), 114 – 123.
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Abstract
Highway construction occasionally takes place in remote locations, making its document management challenging especially when frequent document revisions occur. With the recent advancement of smartphones and tablets, Quick Response (QR) codes can provide project teams rapid and reliable access to up-to-date documents required for field operations. As a result, the use of QR codes can lead to a reduced need for traveling or meeting for document revisions, and reduce the amount of hardcopy documents and storage space. Despite the potential for significant benefits, there have been few studies aimed at assessing the feasibility of using QR codes in highway construction. In response, the objective of the study was to investigate the benefits of and barriers to using QR codes in highway construction for document management. To conduct the study, first a multi-step process was used, involving an online survey and interviews, with a goal of determining the status quo of highway construction in terms of document management and mobile information technology (IT). The results indicate that hardcopy documentation is still the most prevalent form of document management in highway construction, and hence there is an opportunity for implementing QR codes in conjunction with mobile IT. In the second part of the study, a time study using a real-world infrastructure project was conducted based on three activities: detail look up, specification check, and version check. As a result, the study found statistical evidence that using QR codes can lead to significant time savings.
Keywords
Highway Planning; Information Services; Road Construction; Document Management; Field Operation; Highway Construction; Infrastructure Project; Online Surveys; Quick Response Code; Remote Location; Statistical Evidence
Habibnezhad, Mahmoud; Puckett, Jay; Jebelli, Houtan; Karji, Ali; Fardhosseini, Mohammad Sadra; Asadi, Somayeh. (2020). Neurophysiological Testing for Assessing Construction Workers’ Task Performance at Virtual Height. Automation In Construction, 113.
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Abstract
Falling from heights is the primary cause of death and injuries at construction sites. As loss of balance has a fundamental effect on falling, it is important to understand postural regulation behavior during construction tasks at heights, especially those that require precise focus in an upright standing position (therefore, a dual-task demand on focus). Previous studies examined body sway during a quiet stance and dual tasks to understand latent factors affecting postural balance. Despite the success of these studies in discovering underlying factors, they lack a comprehensive analysis of a task's simultaneous cognitive load, postural sway, and visual depth. To address this limitation, this paper aims to examine construction workers' postural stability and task performance during the execution of visual construction tasks while standing upright on elevated platforms. To that end, two non-intrusive neurophysiological tests, a hand-steadiness task (HST) and a pursuit task (PT), were developed for construction tasks in a virtual environment (VE) as performance-based means to assess the cognitive function of workers at height. Workers' postural stability was measured by recording the mapped position of the Center of Pressure (COP) of the body on a posturography force plate, and the postural sway metrics subsequently calculated. A laboratory experiment was designed to collect postural and task performance data from 18 subjects performing the two batteries of tests in the virtual environment. The results demonstrated a significant decrease in the Root-Mean Square (RMS) of COP along the anterior-posterior axis during the Randomized Pursuit Task (RPT) and maximum body sway of the center of pressure (COP) in the mediolateral direction during both tests. Also, subjects exposed to high elevation predominately exhibit higher accuracy for RPT (P-value = 0.02) and lower accuracy for HST (P-value = 0.05). The results show that the combination of elevation-related visual depth and low-complexity dual tasks impairs task performance due to the elevation-induced visual perturbations and anxiety-driven motor responses. On the other hand, in the absence of visual depth at height, high task complexity surprisingly improves the pursuit tracking performance. As expected, during both tasks, alterations in postural control were manifested in the form of a body sway decrement as a compensatory postural strategy for accomplishing tasks at high elevation.
Keywords
Task Performance; Construction Workers; Test Design; Cognitive Load; Standing Position; Sitting Position; Neurophysiological Test; Postural Stability; Virtual Reality; Workers' Safety At Height; Fall-risk; Reaction-time; Fear; Real; Acrophobia; Balance; Safety