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The Performance of Risk Management and Innovation in Construction Manager/General Contractor Delivery in Civil Construction ApplicationsOwens, Rebecca M. 13 December 2013 (has links) (PDF)
Project teams that deliver high risk, complex projects in the civil construction industry need tools to enable successful delivery. Construction Manager/General Contractor (CM/GC) is an innovative alternate delivery method, providing one such a tool. CM/GC furnishes public agencies with an attractive option for delivering projects in a less adversarial and more constructive manner by involving the contractor during design. The sophisticated public owner does not have to relinquish control of the details of the design in order to accelerate the schedule or see the benefits of real-time cost estimating data. There are also significant cost and schedule benefits with not degradation in quality. However, because CM/GC is relatively unknown to the civil construction industry much remains to be investigated about how CM/GC processes effect successful project delivery. This research investigated how CM/GC processes affect the three critical elements of construction process risks (including quality, schedule, cost and collaboration), project specific risks, and innovation. By identifying the processes that benefit these elements, successes can be repeated and increased. Additionally, an understanding of the differences in the perception of CM/GC processes, given by contractors, owners, and design engineers, provided perspective into improving the process. Analyzing data on current CM/GC projects and programs, as well as the compiled experience of field-experienced project teams, provided the information the industry needs to pursue implementation. Identified advantages of the process can be tied to strategies for successful delivery. Identified disadvantages expose barriers to implementation to be overcome by the project team. Project teams state that while the process does have disadvantages, many are perceptional and not fatal flaws to the method. Findings of this research link CM/GC processes to robust risk management results and the opportunity for successful innovation.
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Multi-Rotor--Aided Three-Dimensional 802.11 Wireless Heat MappingPack, Scott James 18 March 2014 (has links) (PDF)
Traditional wireless site surveys produce a heat-map of link strength or quality over a target area, usually on the ground plane. In recent years research has gone into using aerial drones in network attack and surveillance, making three dimensional awareness of wireless coverage areas of interest. A multi-rotor drone and data collection module were built and tested as part of this research. Site assessments were conducted both in open space and near structures. Collected data was interpolated across the target area, and visualized as points and contours. These visualizations were exported to a Keyhole Markup Language (KML) for visualization in context. Resulting visualizations proved to be beneficial in identifying the coverage area of both authorized and rogue access points.
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Termediator-II: Identification of Interdisciplinary Term Ambiguity Through Hierarchical Cluster AnalysisRiley, Owen G. 23 April 2014 (has links) (PDF)
Technical disciplines are evolving rapidly leading to changes in their associated vocabularies. Confusion in interdisciplinary communication occurs due to this evolving terminology. Two causes of confusion are multiple definitions (overloaded terms) and synonymous terms. The formal names for these two problems are polysemy and synonymy. Termediator-I, a web application built on top of a collection of glossaries, uses definition count as a measure of term confusion. This tool was an attempt to identify confusing cross-disciplinary terms. As more glossaries were added to the collection, this measure became ineffective. This thesis provides a measure of term polysemy. Term polysemy is effectively measured by semantically clustering the text concepts, or definitions, of each term and counting the number of resulting clusters. Hierarchical clustering uses a measure of proximity between the text concepts. Three such measures are evaluated: cosine similarity, latent semantic indexing, and latent Dirichlet allocation. Two linkage types, for determining cluster proximity during the hierarchical clustering process, are also evaluated: complete linkage and average linkage. Crowdsourcing through a web application was unsuccessfully attempted to obtain a viable clustering threshold by public consensus. An alternate metric of polysemy, convergence value, is identified and tested as a viable clustering threshold. Six resulting lists of terms ranked by cluster count based on convergence values are generated, one for each similarity measure and linkage type combination. Each combination produces a competitive list, and no clear combination can be determined as superior. Semantic clustering successfully identifies polysemous terms, but each similarity measure and linkage type combination provides slightly different results.
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Current BIM Practices of Commercial MEP ContractorsKent, Bryan John 04 June 2014 (has links) (PDF)
Building Information Modeling (BIM) use in the contracting industry has grown significantly in recent years. With this change in the construction industry, consensus has not been reached as to what BIM is, who is using it and what they are using it for. The purpose of this research was to determine current BIM practices of US-based commercial MEP contractors. Executive, middle management, and field personnel were interviewed to determine the current BIM practices in their companies. The majority of companies interviewed were using BIM and most were using it on a significant portion of their projects. The majority of MEP contractors using BIM were seeing positive results in many of six key performance indicators, profitability, schedule duration, field efficiency, change orders, rework, and safety. The top uses of BIM for MEP contractors were clash detection coordination, prefabrication, design creation, and quantity take-off/cost estimating. Most MEP contractors have not yet incorporated BIM for scheduling, sequencing, or safety analysis. Additionally most MEP contractors did not have a formal BIM training program in their company.
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"The Church and Colonel Saunders": Mormon Standard Plan ArchitectureBradley, Martha Sonntag 01 January 1981 (has links) (PDF)
In the years 1920-80 the Mormon Church developed, expanded and refined an architectural program based on the concept of the standard plan. Standard plan buildings were selected, individualized and built for local ward units under the direction of the Church Building Department which created uniform standards of quality and appearance across the worldwide Church and created a tangible link between foreign members and the central Church.Although functional and financial considerations directed virtually all design decisions and formed the operative basis of the program other elements also determined the nature of the Mormon approach to building. Growth, in the membership, more than any other single factor, affected the nature of building in the Church of Jesus Christ of Latter-day Saints. The mid-century emphasis on the accelerated missionary program, internationalization of the Church, and the emphasis on global uniformity of Church programs led to the use of the standard plan as the exclusive method of new construction in 1980.
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Organizational Learning in Commercial Construction: Lessons Learned from the 2007-2009 U.S. RecessionDanforth, Evan Michael 01 April 2015 (has links) (PDF)
Organizational learning seeks to proactively expand the knowledge base of an organizational entity by incorporating knowledge, skills, and experience into the collective conscience of the company through the development of routines rather than relying on individual employees for these traits. Valuable experience gained by individuals who weather economic downturn with their companies must be absorbed into the corporate structure in a meaningful way so that it may be accessible for use during future recessions. This research asks what was learned by individuals during the most recent recession, what mechanisms were employed to retain and utilize this knowledge, and what cultures, strategies, or processes were created because of it. Companies were also compared to understand whether an increase in organizational learning within a company would translate into increased performance.
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Influence of Material Type, Aggregate Size, and Unconfined Compressive Strength on Water Jetting of CIDH Pile AnomaliesHeavin, Joseph Carl 01 March 2010 (has links) (PDF)
Water jetting as a means for removing anomalous materials from cast-in-drilled-hole (CIDH) piles was examined. The primary objective of this research was to establish empirical relationships between different jetting parameters and the removal of commonly occurring anomalous zone materials, including low-strength concrete, slurry mixed concrete, grout, and clay soil. Also investigated was the current standard-of-practice used by water jetting contractors within California. The testing specimens consisted of typical anomalous material with unconfined compressive strengths between 5 and 6,000 psi. The experimental work consisted of water blasting submerged specimens using rotary jets, nozzles, and pumping equipment typically used in construction practice. Two testing protocols were developed. The first testing protocol called for the nozzle to be held stationary and the second allowed the nozzle to be cycled up and down across the anomaly. During testing, material removal rates were measured as a function of jet pressure and standoff distance. Water blasted specimens were cut apart after testing to confirm erosion measurements and to permit inspection of the water blasted surfaces. Based on the results, erosion rates and the effectiveness of water jetting are primarily influenced by unconfined compressive strength, when using standard test equipment and jetting pressures. Further, aggregate size and material type in the anomalous material does not appear to influence both total erosion and erosion rate.
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Construction Industry Hesitation in Accepting Wearable Sensing Devices to Enhance WorkerFugate, Harrison M 01 June 2022 (has links) (PDF)
The construction industry is one of the most unsafe industries for workers in the United States. Advancements in wearable technology have been proven to create a safer construction environment. Despite the availability of these devices, use within the construction industry remains low. The objective of this research is to identify and analyze the causes behind the reluctance of the construction industry to implement two specific wearable safety devices, a biometric sensor, and a location tracking system. Device acceptance was analyzed from the perspective of the user (construction field labor) and company decision makers (construction managers). A modified unified theory of acceptance and use of technology (UTAUT) model was developed specific to barriers commonly found within technology adoption in the construction industry including: perceived performance expectancy, perceived effort expectancy, openness to data utilization, social influence, data security, and facilitating conditions. A structured questionnaire was designed to test for association between the mentioned constructs and either behavioral intention or actual use. The questionnaire went through an expert review process, and a pilot study was conducted prior to being distributed to industry. Once all data was received Pearson chi-squared analysis was used to test for association between the constructs. A minority (46%) of labor respondents would not agree to voluntarily use the biometric wearable sensing device. Constructs associated with this finding included perceived performance expectancy, perceived effort expectancy, and social influence. A majority (59%) of labor respondents would not agree to voluntarily use the location tracking wearable sensing device. Constructs associated with this finding included perceived performance expectancy, social influence, and data security. A majority (56%) of management respondents would not implement the biometric wearable sensing device. Constructs found to be associated with this finding included perceived performance expectancy, openness to data utilization, and social influence of the client. A supermajority (68%) of management respondents would not implement the location tracking wearable sensing device. Constructs found to be associated with this finding include perceived performance expectancy, perceived effort expectancy, openness to data utilization, social influence, and data security. This study will aid in the successful implementation of wearable sensing devices within the construction industry. Findings from this study can be used to aid those hoping to implement wearable sensing devices by identifying causes of wearable sensing device rejection. The results of this study can be used by both project managers and health and safety professionals to aid in device acceptance by field labor, and by those whose goal is to increase device use among construction firms.
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STRENGTHENING OF RC BEAMS WITH EXTERNALLY BONDED AND ANCHORED FRP LAMINATECameron, Ryne 10 1900 (has links)
<p>Premature debonding of externally bonded FRP laminate from retrofitted reinforced concrete (RC) members can lead to inefficient use of FRP and can limit the level of strength increase that can be achieved. In this investigation, novel carbon FRP anchors were used in an attempt to delay the onset of premature debonding and to achieve superior strength. Nine double shear tests were performed on small scale concrete prisms to determine the most suitable epoxy for bonding the anchors to the laminate and the concrete. One type of epoxy increased the ultimate load of the prism retrofitted with two anchors at each end of the laminate 83.7% over the control specimens without anchors. The second phase of the investigation consisted of testing six large scale T-beams with a 4500 mm span, 400 mm height and 500 mm flange width under four point bending. Two beams were tested without FRP reinforcement as control beams, one beam was tested with FRP only epoxy bonded and the remaining three beams were tested with the FRP epoxy bonded and anchored. One of the beams with 30 anchors exhibited a 46% increase in the debonding load over the beam without anchors while the FRP laminate attained a maximum strain equal to 80% of its ultimate strain capacity, a 94% increase over the beam strengthened with only epoxy bonded FRP. The results demonstrate the anchoring system’s effectiveness and a feasible way to efficiently utilize the FRP laminate.</p>
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Inelastic Response of Reinforced Concrete Frames to Seismic Ground Motions Having Different CharacteristicsZhu, Tian-Jian 11 1900 (has links)
<p>Observations of structural damage following recent major earthquakes have indicated that ground motion characteristics have a significant effect on the damage of building structures. An analytical study is undertaken to investigate the effect of ground motion characteristics on the inelastic response of multistorey reinforced concrete frame structures and to evaluate the seismic performance of reinforced concrete frame structures designed in conformance with current Canadian seismic provisions. In addition, the possibility of using simplified analysis procedures to estimate inelastic response is studied for regular building frames subjected to different types of earthquake ground motions.</p> <p>An earthquake data set consisting of 45 horizontal components of strong motion records is selected and subdivided into three groups representative of seismic ground motions having low, intermediate, and high peak acceleration-to-velocity (A/V) ratios. This data set is analyzed to investigate the significance of the A/V ratio as a parameter to indicate the dynamic characteristics of earthquake ground motions resulting from different seismic environments. Four regular moment resisting reinforced concrete building frames having different fundamental periods are designed for combined gravity and seismic effects determined in accordance with the 1985 edition of the National Building Code of Canada (NBCC 1985). The structural members are proportioned and detailed to satisfy the requirements of the 1984 edition of the Canadian Concrete Code (CAN3-A23.3-H84). These four frames are used as structural models having very short, short, moderate, and long fundamental periods.</p> <p>To gain insight into the inelastic behaviour of the designed frames, the inelastic static responses of the frames to monotonically increased lateral loading are examined first. Following this inelastic static analysis, the inelastic dynamic responses of the frames to the three A/V groups of earthquake accelerograms are analyzed statistically. In addition, the elastic dynamic responses of the frames to the three A/V groups of earthquake records are obtained to provide a reference for the evaluation of the inelastic dynamic responses. In the course of the dynamic analyses, overall energy indices are defined for multistorey building frames and their numerical computation is implemented in a computer program.</p> <p>A simplified analysis procedure is proposed to estimate both overall and localized inelastic deformations for regular building frames. This simplified analysis procedure is evaluated based on a comparison of the inelastic deformational demands estimated from the procedure with the statistical results obtained from the inelastic dynamic analysis of the frames.</p> / Doctor of Philosophy (PhD)
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