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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The hydraulic efficiency of road drainage gratings

Davis, Alastair C. January 1997 (has links)
No description available.
2

One dimensional compression behaviour of unsaturated granular soils at low stress levels

Goodwin, Andrew Keith January 1991 (has links)
No description available.
3

Cost Effective Quality Assurance Practices in Highway Construction

Newland, James M 01 August 2015 (has links)
The estimated value of the U.S. transportation infrastructure is over $7.0 trillion. The challenge is preserving the quality of the investment. State and federal departments of transportation have methods and procedures for best quality, but vary significantly. With the variations comes opportunity to assess the cost-effectiveness of different strategies and make recommendation on practices that are most successful. A survey was created and sent to all 50 states and the District of Columbia. The survey was aimed to capture information on construction finished product testing methods, optimized/reduced sampling techniques, innovative QA practices that measure multiple performance criteria and QA processes that are rapid and cost effective. There are many testing methods and procedures being used throughout the U.S. This thesis will allow state and federal transportation agencies to look at the findings and possibly implement them into their own agency with hopes of saving time and money for future projects.
4

Critical Analysis of Current Practices of Highway Construction Cost Index (HCCI) Calculation and Utilization

Shrestha, Joseph, Jeong, H. David, Gransberg, Douglas D. 01 January 2016 (has links)
A proper understanding of the local construction market is essential for making appropriate project budgeting and planning decisions. State highway agencies typically use highway construction cost indexes (HCCIs) to understand the current market conditions. In the U.S. highway construction industry, the Federal Highway Administration (FHWA) pioneered the concept of a HCCI as an indicator of the national construction market. State Departments of Transportation (DOT) also started developing their state level HCCIs to better represent their state level construction markets. But, some state DOTs noted the lack of guidance to develop and update their HCCIs. This paper summarizes literature review and nationwide questionnaire survey results to identify the current practices of calculating and using HCCIs. There are two methods to generate basket of construction items for HCCI calculation: a) categorized market basket and b) item level market basket. The Fisher index is the most popular indexing formula among the state DOTs and is also recommended by the FHWA and International Monetary Fund (IMF). Despite many potential users of HCCIs, the current use of HCCIs is very limited in state DOTs.
5

The Local Interest as a Consideration in the Planning of Highway Construction in the Canyonlands Region of Southeastern Utah

Barry, Robert L. 01 May 1973 (has links)
An examination was conducted of the potential of proposed highway construction for serving the needs and interests of the population of the Canyonlands Region of southeastern Utah. The history of the highway development issue in the region was first examined with special attention given to the local position on the issue as expressed by local government spokesmen. Next, the total system of development proposals for the region was divided into four sections using criteria of area served and degree of controversy. A map analysis was conducted to determine how these four separate proposals would serve transportation needs of the region. Travel data for 1971 Utah nonresident travelers were utilized to determine present tourism travel and expenditure patterns within the region. Projections were made as to how these patterns would be altered by the four proposals and of how such alterations would affect the tourism industry in the five Canyonlands counties. Region resident perceptions of how the proposals would serve transportation, tourism development, and general economic needs of the region, its counties, and communities were obtained from 231 questionnaires. The same instruments also examined resident preferences for route development. The analyses indicated that the proposed developments will have few effects on regional transportation needs, and that the impact on the tourism industry will be substantial in some areas within the region and negligible in others. Resident expectations of which proposals would best meet county, community, and household needs were generally realistic. Residents assigned priority for development to proposals anticipated to best serve needs at these levels. Regional needs were not clearly perceived and were not important in determining development preferences. The position on the highway development issue taken by local government leaders distorts the views of residents but does so in a way which generally serves the local interest.
6

Hydraulic performance of temporary construction traffic barriers

Hudson, Cody Brent 26 October 2010 (has links)
Temporary Concrete Traffic Barriers (TCTBs) are essential in order to protect the traveling public and highway construction crews from accidents due to driver misfortune or negligence. In order for TCTBs to be installed, however, they must be successfully crash tested. Barrier height and drainage open space are key characteristics that influence this crash test rating. This is because an increase in height will insure that a vehicle will not over-top the barrier and a decrease in drainage open space will result in greater barrier mass, which will in turn resist larger impact forces. The factors that increase the crash worthiness of a barrier, however, lead to poor hydraulic performance. This then becomes a concern if barriers are placed in areas where they may adversely impact the local floodplain elevation. The objective of this research is the development of a hydraulic rating curve that describes the relationship between upstream energy head and the flow rate passing the barrier. To accomplish this objective, a three parameter model with three unknown coefficient terms was utilized. The model was then fit to experimentally obtained data, and a rating curve was developed. In addition, the effects of downstream submergence and clogging of the drainage opening, with respect to the rating curve, was also analyzed. Finally, a method for using this information in the hydraulic modeling software HEC-RAS was developed. / text
7

Risk factors leading to cost overrun in the delivery of highway construction projects

Creedy, Garry D. January 2006 (has links)
Accurate client budget estimates are critical to the initial decision-to-build process for the highway construction projects. This decision-to-build point in a project's development is seen as the international standard for measuring any subsequent cost estimate inaccuracies involved (National Audit Office/Department of Transport, 1992; World Bank, 1994; Nijkamp and Ubbels, 1999), with accuracy being defined as the difference between the initial project estimate at the decision-to-build stage and the real, accounted project cost determined at the time of project completion. Expressed as a percentage of estimated cost, this is often termed cost escalation, cost overrun or cost growth, and occurs as a result of many factors, some of which are related to each other, but all are associated with forms of risks. The analysis of these risks is often a necessary step for the improvement of any given estimating system and can be used to diagnose trouble spots and to pinpoint areas where project estimating accuracy improvement might be obtained. In this research, highway projects in Queensland, Australia that have suffered significant cost overrun are analysed. The research seeks to address the gap in the knowledgebase as to why highway projects overrun their costs. It focuses on understanding how client projects budgets go wrong, when dealing with project risk. The foundation for this research is drawn from the post-mortem analysis of highway projects, each costing in excess of A$1m and whose final total expenditure exceeded budget by 10% or greater. The research identifies client risk variables which have contributed to significant cost overrun and then uses factor analysis and also expert elicitation, using nominal group technique, to establish groups of importance ranked client risks. Stepwise multivariate regression analysis is then used to investigate any correlation of these risks, along with project attributes such as highway project type, indexed project cost, geographic location and project delivery method to the percentage of cost overrun. The research results indicates a correlation between the reciprocal of project budget size and percentage cost overrun that can be useful in clients determining more realistic decision-to build highway budget estimates when taking into account project size in relation to economy of scale.
8

Evaluation of Sulfidic Materials in Virginia Highway Corridors

Orndorff, Zenah W. 09 October 2001 (has links)
Road construction through sulfidic materials in Virginia has resulted in localized acid rock drainage (ARD) that threatens water quality, fill stability, integrity of building materials, and vegetation management. The objectives of this study were: i) to develop a state-wide sulfide hazard rating map based on characterization of the geologic formations associated with acid roadcuts, ii) to estimate depth to sulfidic sediments in the Coastal Plain based on landscape relationships, and iii) to evaluate potential acidity testing procedures on diverse materials. Geologic formations associated with acid roadcuts were characterized by potential peroxide acidity (PPA) and S content, and grouped into four categories. Listed in order of increasing severity, these formations included: the Tabb Formation (Coastal Plain), the Lynchburg Group of the Ashe Formation (Blue Ridge), the Chesapeake Group and Lower Tertiary deposits (Coastal Plain), the Millboro shale, Marcellus shale, Chatanooga shale and Needmore Formation (Valley and Ridge), and the Quantico Formation (Piedmont). Evaluation of landscape parameters near Richmond, Virginia, indicated that the likelihood of encountering sulfidic materials within a given depth at a specific location was related to elevation and mapped soil types. Elevation and soil map units were assigned to risk classes to indicate the likelihood of encountering sulfides within a depth of 9 m. Comparison of PPA and S content for 296 diverse samples indicated that S may serve as a screening tool to evaluate materials without carbonates. Comparison of PPA and conventional Acid-Base Accounting (ABA) for 14 diverse samples indicated that PPA and ABA were highly correlated, with PPA yielding 0.60 to 0.95X the amount of acidity as ABA. Potential acidity by Soxhlet extraction and PPA were equivalent for 3 of 4 diverse samples. Average acidity and metal contents of leachate from Soxhlet extractors were correlated with acidity and metals of road drainage. Sulfide hazard analysis should be an essential step in the pre-design phase of highway construction and other earth-disturbing activities. / Ph. D.
9

Multidimensional Highway Construction Cost Indexes Using Dynamic Item Basket

Shrestha, Joseph, Jeong, H. David, Gransberg, Douglas D. 01 August 2017 (has links)
A highway construction cost index (HCCI) is an indicator of the purchasing power of a highway agency. Thus, it must reflect the actual construction market conditions. However, current methods used by most state departments of transportation are not robust enough to meet this primary goal due to (1) a significantly insufficient sample size of bid items used in HCCI calculation; and (2) inability to address the need to track highway construction market conditions in specific submarket segments such as, but not limited to, various project types, sizes, and locations. This study proposes an advanced methodology to overcome these apparent limitations using two new concepts: (1) dynamic item basket; and (2) multidimensional HCCIs. The dynamic item basket process identifies and utilizes an optimum amount of bid-item data to calculate HCCIs in order to minimize the potential error due to a small sample size, which leads to a better reflection of the current market conditions. Multidimensional HCCIs dissect the state highway construction market into distinctively smaller sectors of interest and thus, allow state Departments of Transportation to understand the market conditions with much higher granularity. A framework is developed to integrate these two concepts and a standalone prototype system, named the Dyna-Mu-HCCI System, is developed to automate the data-processing part of the framework. The historical bid data of the Montana Department of Transportation are used to evaluate the performance of the Dyna-Mu-HCCI System and measure the effects of the dynamic item basket (DIB) and multidimensional HCCIs. The results show an eightfold increase in terms of the number of bid items used in calculating HCCIs and at least a 20% increase in terms of the total cost of bid items used. In addition, the multidimensional HCCIs reveal different cost-change patterns from different highway sectors. For example, the bridge construction market historically shows a very different trend compared with the overall highway construction market. The new methodology is expected to aid state Departments of Transportation in making more-reliable decisions in preparing business plans and budgets with more accurate and detailed information about the construction market conditions. Further, the prototype Dyna-Mu-HCCI System is expected to significantly facilitate the HCCI calculation process and rapidly implement this new system.
10

The Local Interest as a Consideration in the Planning of Highway Construction in the Canyonlands Region of Southeastern Utah

Barry, Robert L. 01 May 1973 (has links)
An examination was conducted of the potential of proposed highway construction for serving the needs and interests of the population of the Canyonlands Region of Southeastern Utah. The history of the highway development issue in the region was first examined with special attention given to the local position on the issue as expressed by local government spokesmen. Next, the total system of development proposals for the region was divided into four sections using criteria of area served and degree of controversy. A map analysis was conducted to determine how these four separate proposals would serve transportation needs of the region.

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