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<title>Papers in Construction Management</title>
<copyright>Copyright (c) 2013 University of Nebraska - Lincoln All rights reserved.</copyright>
<link>http://digitalcommons.unl.edu/constructionmgmt</link>
<description>Recent documents in Papers in Construction Management</description>
<language>en-us</language>
<lastBuildDate>Thu, 24 Jan 2013 13:37:41 PST</lastBuildDate>
<ttl>3600</ttl>








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<title>A TRADE CONSTRUCTION KNOWLEDGE MODULE TO ENABLE
USE OF DESIGN COMPONENT DATA IN PROJECT
MANAGEMENT</title>
<link>http://digitalcommons.unl.edu/constructionmgmt/10</link>
<guid isPermaLink="true">http://digitalcommons.unl.edu/constructionmgmt/10</guid>
<pubDate>Fri, 08 Jun 2012 08:02:35 PDT</pubDate>
<description>
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	<p>The complexity, tight budget, and dynamic market of today's construction project require the seamless integration of both design and construction data, However, despite the availability of both digital design tools (various CAD applications) and digital project management tools (such as schedule software and construction management software), design data has to still be entered manually into construction applications. In order to close this gap, CAD applications widely used in AEC industries are evolving toward providing the product data within the CAD package itself, in addition to the existing graphic-oriented data. While useful, those new data-driven CAD applications are largely design-oriented and are still hardly used directly in construction practices. In this research, a detailed case study is presented and analyzed to demonstrate the limitations of the current data-driven CAD application when used to support construction management. To address the limitations, a trade construction knowledge module using a specific product model is under development to provide domain views for different trades.</p>

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<author>Zhigang Shen et al.</author>


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<title>Complex Engineering System Learning through
Study of Engineering Failure Cases using 3D
Animations</title>
<link>http://digitalcommons.unl.edu/constructionmgmt/9</link>
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<pubDate>Fri, 08 Jun 2012 07:56:57 PDT</pubDate>
<description>
	<![CDATA[
	<p>Complex engineering systems often require dynamic coordination of multidisciplinary teams with conflicting objectives. Failing to understand the complex relationships among the conflicting objectives may result in serious engineering failures. In engineering education, one of the challenges in teaching complex systems is the lack of effective tools to demonstrate system dynamics, especially spatial-temporal relationships in the system. The described project in this paper is supported by grants from Engineering Education program of the National Science Foundation. In the project civil/construction engineering cases are used as the context to test the proposed new teaching/learning tool on the subject and to demonstrate the effectiveness of the developed tool. In building system design, structural designs mainly focus on the behavior of structures under design loads specified for operating stage. Typically less attention is given to the dynamic transient load during various construction stages. The insufficient considerations of the construction related transient loads may reach the critical point during construction and cause structural failure. For example, there were cases of bridge collapse during construction due to inadequate considerations of the load dynamics during construction. Also, many factors affecting construction transient loads were not technical. Rather, they are management related such as construction sequence and cost considerations. Thus, enabling construction students to learn from the similar cases through effective media is critical to avoid repeating the mistakes.</p>

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<author>Zhigang Shen et al.</author>


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<title>A case-crossover study of laceration injuries
in pork processing</title>
<link>http://digitalcommons.unl.edu/constructionmgmt/8</link>
<guid isPermaLink="true">http://digitalcommons.unl.edu/constructionmgmt/8</guid>
<pubDate>Thu, 07 Jun 2012 13:32:28 PDT</pubDate>
<description>
	<![CDATA[
	<p>Objectives— The authors estimated the associations between transient risk factors and laceration injuries in workers at two meatpacking plants in the Midwest.</p>
<p>Methods— The case-crossover design was used to collect within-subject transient work task and personal-level exposure information. RRs of laceration injuries were estimated by comparing exposures during the ‘hazard’ period (just before the laceration injury) with exposures in the ‘control’ period (the previous workweek). Stratified analyses were utilized to estimate the effects of gender, ethnicity, training and the number of adjacent coworkers on each transient risk factor.</p>
<p>Results— The authors interviewed 295 meatpacking workers with laceration injuries (mean age 36.6 years, SD 11.2, 75% men, 48% Hispanic). Recent tool sharpening (RR 5.3, 95% CI 3.8 to 7.4) and equipment malfunction (RR 5.3, 95% CI 3.9 to 7.3) were associated with the highest RR for laceration injury, followed by using an unusual work method to accomplish a task (RR 4.1, 95% CI 2.6 to 6.4) and performing an unusual task (RR 2.3, 95% CI 1.8 to 3.0). Rushing and being distracted were not significantly associated with an elevated RR of a laceration injury. In stratified analyses, there were a number of significant differences in laceration risk factors by gender, ethnicity, training, and number of workers on the line.</p>
<p>Conclusions— Sharpening tools, equipment malfunction, using an unusual work method to accomplish a task and performing an unusual task were all associated with increased risk of lacerations. Expanded training in atypical work circumstances and evaluation of tool sharpening procedures are intervention areas in meatpacking that need examination.</p>

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</description>

<author>Lina Lander et al.</author>


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<title>A Model for Integrating Construction Design
and Schedule Data</title>
<link>http://digitalcommons.unl.edu/constructionmgmt/7</link>
<guid isPermaLink="true">http://digitalcommons.unl.edu/constructionmgmt/7</guid>
<pubDate>Fri, 09 Dec 2011 12:55:17 PST</pubDate>
<description>
	<![CDATA[
	<p>The difficulty of timely retrieval of useful information from heterogeneous data sources is a major cause of low productivity in the construction industry. The goal of this research is to provide a new methodology to handle the data-heterogeneity problems encountered in a construction project. This research proposes a tree-structured product model, which binds design knowledge, cost data and schedule data together, as a feasible solution for the data integration problem in construction projects. The methodology uses the knowledge representation of construction projects based on an ontology. Metadata are used to describe the conceptual structure of the project knowledge. The concept of views is used to answer particular queries from different domains.</p>
<p>A general methodology is under development to support queries about a particular construction project from different user perspectives based on heterogeneous construction data sources in a dynamic environment. The research is composed of two major parts: (1) organize the heterogeneous construction data into a tree structure; and (2) retrieve information and obtain domain views by specifying the ways of traversing the tree. The future goal is to develop a prototype that will support some of the major functions needed in today’s construction projects. Functional examples are used to demonstrate the validity of the proposed methodology.</p>

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<author>Zhigang Shen et al.</author>


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<title>A Building LCA Case Study Using Autodesk Ecotect and BIM Model</title>
<link>http://digitalcommons.unl.edu/constructionmgmt/6</link>
<guid isPermaLink="true">http://digitalcommons.unl.edu/constructionmgmt/6</guid>
<pubDate>Mon, 05 Dec 2011 08:39:35 PST</pubDate>
<description>
	<![CDATA[
	<p>The main objective of this study is to evaluate the potential of utilizing building information model (BIM) to perform whole building Life Cycle Analysis (LCA). The research question addressed was how life cycle performance of a building was affected quantitatively by design configurations. Life cycle energy consumption and CO<sub>2</sub> emission of a university building in the Midwest was calculated using Autodesk® Ecotect and BIM model. The study compared life cycle performance, i.e., CO<sub>2</sub> emissions and energy consumptions, among different design configurations, as well as their distributions in the stages of the building’s life time. Sensitivity analysis was performed by changing several alternative parameters, to identify which parameter has more impacts on building performance. Preliminary results indicated that whole building life cycle performance is affected by several design parameters, with different degree of sensitivity. The conclusions of the study are: 1) The combination of Ecotect and BIM model provides a convenient tool to conduct whole building LCA through the easier data flow from the BIM model to Ecotect. The data entry workload for whole building LCA can be reduced significantly. 2) Energy consumption in the operating stage dominates the lifecycle energy consumption of the building. 3) Sensitivity analysis of impact of design change can be conducted using the combination of Ecotect and BIM model.</p>

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</description>

<author>Endong Wang et al.</author>


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<title>Limited Scope Permitting for Time-Sensitive Project Delivery Systems</title>
<link>http://digitalcommons.unl.edu/constructionmgmt/5</link>
<guid isPermaLink="true">http://digitalcommons.unl.edu/constructionmgmt/5</guid>
<pubDate>Mon, 05 Dec 2011 08:36:32 PST</pubDate>
<description>
	<![CDATA[
	<p>Delivery of construction projects in the United States has traditionally been based upon the design-bid-build system. TIlis system has been used to create numerous impressive structures, but it often proves expensive and usually requires considerable time, because design, permitting and construction are accomplished in sequential order and do not overlap. Several alternatives to the traditional system have been developed, many of which fall under the classification of time-sensitive project delivery systems. The most commonly used time-sensitive project delivery systems are phased and fast-track construction (FaZio, Moselhi, Theberge & Revay 1988a). Figure 1 illustrates some of the major differences between traditional design-bid-build and two time-sensitive project delivery systems.</p>
<p>Phased construction is carried out by overlapping work packages, such a, excavation, foundations, structural steel, etc. Each work package is completed by the designer(s) in chronological sequence, with early activities beginning (or sometimes completed) before design is finalized for later work. Design and construction within a single work package do not overlap (Fazio, Moselhi, Theberge & Revay 1988b).</p>
<p>Fast-tracking is accelerated phased construction. Design and construction activities within individual work packages are overlapped to further reduce project duration (Fazio et al 1988b). Since the total scope of work for some activities is unknown until relatively late in the design process, bidders must often formulate estimates based, at least partially, upon anticipated quantities. When fast-tracking a project for construction, the owner must ensure that contract documents completed later in the design process are consistent with documentation used to begin actual construction.</p>
<p>Time-sensitive construction focuses on integrating design, permitting, and construction schedules to capture some of the time lost in the traditional design-bid-build environment. Time-sensitive construction does not shorten the length of time required to complete the individual tasks of creating plans and drawings, acquiring building permits, or actual construction. Instead, design and construction professionals are integrated into a collaborative environment where many of these tasks can be completed (at least somewhat) concurrently.</p>
<p>Rather than the fragmented levels of responsibility which exist under the traditional design-bid-build contracts, phased and fast track contracts often assign responsibility for all details of design and construction to a single entity. This contractual arrangement, known as design-build or design-</p>
<p>Phased and fast-track construction, while not focused on reducing construction cost, often produce savings for the owner and/or contractor. The combined effects of paying for a construction loan (which usually has a higher interest rate than more permanent financing) and an earlier completion date (which can save labor hours) may enhance the overall profitability of a proposed project to the extent that an economically infeasible endeavor can be transformed into reality (Russell & Ranasinghe 1991).</p>
<p>The traditional system of granting legal approval (a permit) to construct a project was, however, created in the early 20th century. This system was designed specifically to protect the public's safety, health and general welfare from less than adequate design, materials and workmanship sometimes encountered when using the traditional design-bid-build project delivery system. The traditional building permitting system, although sometimes viewed as slow, cumbersome and expensive, has proven itself versatile, flexible and responsive to protecting the safety, health and well-being of the public.</p>
<p>When applying for a traditional building permit, all plans, drawings and specifications must be completed, reviewed and approved prior to a full permit being issued. Under the limited scope permitting process now being applied to many time-sensitive projects, construction is divided into different work packages consisting of chronologically phased activities. Only the plans, drawings and specifications pertaining to a specific package must be completed, submitted and approved prior to work beginning on activities within that package (City of Lincoln 2008). An additional limited scope permit is required for each subsequent work package.</p>
<p>The ad vantages inherent in time-sensitive construction have convinced many US municipalities to legally recognize one or more of its variants as a legitimate delivery system for new construction (City of Ithica 2000; Los Alamos County 2006). Other jurisdictions restrict time-sensitive construction to alteration or repair work (City of Columbus 2009). A third set of municipalities recognizes that time-sensitive construction can be appropriate for both new construction and for renovation work. The most common method of legally authorizing time sensitive construction is use of a limited scope permit. The limited scope permitting process is being used by other municipalities to encourage economic growth and competitive development. Afaster and more efficient permit process designed to accommodate developing and expanding businesses provides an incentive for new business and industry to locate in the local area and for existing businesses to expand (City of College Station 2004).</p>
<p>Municipalities are, however, reluctant to incur additionalliability as the result of limited scope permitting. The City of Lincoln's building code specifies" ...you will receive only one set of plans endorsed by stamp indicating that you may, at your own risk, place footings and foundations to grade level only and place underground utilities ... " (City of Lincoln 2008). This wording is an example of a municipality using the limited scope permit to distribute risk among the contractor, designer( s) and owner. These three parties are assuming the risk for placing utilities, foundations and/ or footings because the municipality has no method of checking whether or not the footings, foundations or utilities will conform to the minimum code specifications required for the completed structure. The limited scope permit thus protects the municipality should the utilities, footings or foundations not comply with parameters required by building code for the eventual use of the structure.</p>

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<author>Wayne Jensen et al.</author>


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<title>QUANTITATIVE EVALUATION OF THE BIM-ASSISTED
CONSTRUCTION DETAILED COST ESTIMATES</title>
<link>http://digitalcommons.unl.edu/constructionmgmt/4</link>
<guid isPermaLink="true">http://digitalcommons.unl.edu/constructionmgmt/4</guid>
<pubDate>Mon, 05 Dec 2011 08:31:50 PST</pubDate>
<description>
	<![CDATA[
	<p>The increased interest in using Building Information Modeling (BIM) in detailed construction cost estimates calls for methodologies to evaluate the effectiveness of BIM-Assisted Detailed Estimating (BADE) tools in generating detailed construction cost estimates. The focus of this study is on developing a quantified evaluation method to measure the impact of these BADE tools. Further, in order to understand the cognitive details of the estimator, this study also tested and evaluated the impact of the visualization factor and the compound impact of the visualization factor and aggregated calculation factor on the construction cost-estimating process. Two types of BADE tools were tested in this study in order to differentiate the impact of the visualization factor on estimating performance from the compounded impact of both visualization and aggregation functions. A set of test cases with different levels of estimate complexity was designed and tested on entry-level estimators using both traditional manual estimating and BADE approaches. Results obtained from the test cases at several complexity levels helped to reinforce the reliability of the observations and the evaluation. Four parameters were used to evaluate the performance results individually in the first step: generality, flexibility, efficiency, and accuracy. Then a multi-attribute utility model, which took into account the four individual parameters, was developed and used to evaluate the overall performance of BIM-assisted estimating versus the performance of the traditional estimating method on quantity takeoffs. The study concluded that the BIM-assisted estimate demonstrated better performance over traditional estimating methods for the entry-level user. Both the visualization and aggregation functions of the BADE tool had significant impact on the performance of the detailed estimate. The study further indicated that the more complex the estimating tasks, the clearer the advantages were of using BADE tools instead of traditional estimating methods. The limitations of the test cases and the test subjects will affect the extrapolation of the conclusions of this research to the broad construction industry. Further study on industry-level cases and subjects is needed to obtain more conclusive findings.</p>

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<author>Zhigang Shen et al.</author>


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<title>Measuring Performance of Innovative Pavement Features</title>
<link>http://digitalcommons.unl.edu/constructionmgmt/3</link>
<guid isPermaLink="true">http://digitalcommons.unl.edu/constructionmgmt/3</guid>
<pubDate>Mon, 05 Dec 2011 08:27:38 PST</pubDate>
<description>
	<![CDATA[
	<p>The Nebraska Department of Roads (NDOR) conducts annual examinations of the state's interstate and federal highway pavements. During these examinations, numerous indicators of pavement performance are measured directly or compiled from parameters recorded by a vehicle passing over the pavement section. Parameters are documented and analyzed for each one-tenth mile pavement segment. Seven sections where innovative features have been incorporated into the pavement were selected by the NDOR for comparison to nearby conventional pavement sections. This study used various parameters recorded by the NDOR as well as field observations to compare the performance of seven pairs of pavement sections. Each pair contained one section of pavement with innovative features and a second section of more conventional design.</p>
<p>Pavement performance indicators measured and analyzed included Nebraska Serviceability Index, International Roughness Index, Present Serviceability Index, cracking index, rutting and faulting, plus longitudinal and transverse cracking. The study indicates that pavement sections that had innovative features incorporated generally performed better than pavement sections where more conventional design was used.</p>

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<author>Wayne Jensen et al.</author>


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<title>Semantic 3D CAD and Its Applications in Construction Industry — An Outlook of Construction Data Visualization</title>
<link>http://digitalcommons.unl.edu/constructionmgmt/2</link>
<guid isPermaLink="true">http://digitalcommons.unl.edu/constructionmgmt/2</guid>
<pubDate>Mon, 05 Dec 2011 08:24:43 PST</pubDate>
<description>
	<![CDATA[
	<p>In response to the need of using electronic design data directly in construction management applications, many CAD developers have started implementing semantic data models in their CAD products using industry foundation classes (IFCs). While helpful, these semantic CAD applications have limitations when used in actual construction practices. The case studies in the thesis indicated that: 1) the semantics of the current data model (IFC as an example) is not rich enough to cover the richer details of the real trade practices; 2) the current implementation of the semantic data model lacks the mechanism to provide multiple trades views at various detailed levels. This paper also provided suggestions for the future development of semantic data model of construction industry.</p>

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<author>Zhigang Shen et al.</author>


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<title>The aerodynamic behaviour of respiratory
aerosols</title>
<link>http://digitalcommons.unl.edu/constructionmgmt/1</link>
<guid isPermaLink="true">http://digitalcommons.unl.edu/constructionmgmt/1</guid>
<pubDate>Mon, 05 Dec 2011 08:22:06 PST</pubDate>
<description>
	<![CDATA[
	<p>Hospital acquired infections (HAIs) claim on average 90,000 lives each year in the U.S., nearly three times the number of annual highway deaths. Although fewer than 15% of HAIs are directly attributable to airborne transmission, more than a third may be caused by surface microbes aerosolized by the movement of air from building systems, people and equipment. As a result, a study was devised to use a synthetic respiratory aerosol to track the movement airborne contagion with respect to various environmental conditions in a healthcare environment.</p>

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<author>Kristin K. Grosskopf</author>


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