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Articles 4231 - 4260 of 6342

Full-Text Articles in Engineering

Evaluation Of Us 119 Pine Mountain Safety Improvements (Interim Report), Jerry G. Pigman, Kenneth R. Agent Oct 2003

Evaluation Of Us 119 Pine Mountain Safety Improvements (Interim Report), Jerry G. Pigman, Kenneth R. Agent

Kentucky Transportation Center Research Report

The safety improvement project for a section of US 119 across Pine Mountain in Letcher County was initiated as an interim effort to address safety issues related to roadway geometrics and specific problems related to truck traffic. The project involves sections of the road being improved over a 7.2-mile length at a cost of approximately $36 million.

The Transportation Center at the University of Kentucky was requested to perform an evaluation of the safety improvement project on US 119 to determine whether the types of improvements undertaken have affected the overall safety of the roadway. Specific objectives were as follows; …


Evaluation And Analysis Of Highway Pavement Drainage, Kamyar C. Mahboub, Yinhui Liu, David L. Allen Oct 2003

Evaluation And Analysis Of Highway Pavement Drainage, Kamyar C. Mahboub, Yinhui Liu, David L. Allen

Kentucky Transportation Center Research Report

This report presents an analysis of pavement drainage using various finite element models. The analysis included a range of pavement materials and drainage parameters. The computational tool in study was the SEEP/W option in the GEOSLOPE computer program. A steady-state saturated flow analysis was employed to generate flow paths and flux quantities through the cross-sectional area of the pavement. Finite element models in this study covered various drainage practices and quantified their relative drainage advantages. Finally, recommendations were provided for optimum drainage practices as well as future research topics in this area.


Evaluation Of Methods To Protect Water Quality In Karst Areas: Phase I, Jennifer Webster, Dhandayudhapani Ramalingam, Sudhir Palle Oct 2003

Evaluation Of Methods To Protect Water Quality In Karst Areas: Phase I, Jennifer Webster, Dhandayudhapani Ramalingam, Sudhir Palle

Kentucky Transportation Center Research Report

The primary focus of this report is two-fold; to provide a literature review on what has been previously learned about highway runoff in relation to karsts aquifers and to characterize a karsts highway site in Kentucky that can be used to evaluate a variety of best management practices. From research findings, the main sources of pollutants in highway runoff came from vehicles, atmospheric fallout, and precipitation. The behavior of pollutants and their interaction with the environment can dictate where they will be found and how to best minimize their effects. Although it would seem that traffic volumes would greatly influence …


Analysis Of Traffic Crash Data In Kentucky (1998 – 2002), Kenneth R. Agent, Jerry G. Pigman, Monica L. Barrett, Eric R. Green Sep 2003

Analysis Of Traffic Crash Data In Kentucky (1998 – 2002), Kenneth R. Agent, Jerry G. Pigman, Monica L. Barrett, Eric R. Green

Kentucky Transportation Center Research Report

This report documents an analysis of traffic crash data in Kentucky for the years of 1998 through 2002. A primary objective of this study was to determine average crash statistics for Kentucky highways. Average and critical numbers and rates of crashes were calculated for various types of highways in rural and urban areas. These data can be used in Kentucky’s procedure to identify locations that have abnormal rates or numbers of crashes.

The other primary objective of this study was to provide data that can be used in the preparation of the problem identification portion of Kentucky’s Annual Highway Safety …


Simulation Of Fixed– And Variable–Rate Application Of Granular Materials, John Patrick Fulton, Scott A. Shearer, Timothy S. Stombaugh, Michael E. Anderson, Thomas F. Burks, Stephen F. Higgins Sep 2003

Simulation Of Fixed– And Variable–Rate Application Of Granular Materials, John Patrick Fulton, Scott A. Shearer, Timothy S. Stombaugh, Michael E. Anderson, Thomas F. Burks, Stephen F. Higgins

Biosystems and Agricultural Engineering Faculty Publications

Research has shown that application errors exist with variable–rate technology (VRT) systems. Consequently, using prescription maps for economic and agronomic analyses can generate misleading results. The intent of this article was to develop and validate a spatial data model for generating “as–applied” maps to support the advancement of precision agriculture practices. Previous research modified ASAE Standard S341.2 to include a 2–D matrix of collection pans to assess fixed–rate and variable–rate (VR) deposition of granular fertilizers and agricultural lime from a spinner disc spreader. The “as–applied” spatial data model uses GIS functionality to generate “as–applied” surfaces by merging distribution patterns and …


Evaluation Of Working Capacity For Disadvantaged Business Enterprises (Dbe) For Highway Construction In Kentucky, Fy 2004 Update, Brad W. Rister, Raymond F. Werkmeister, Paul E. Toussaint Aug 2003

Evaluation Of Working Capacity For Disadvantaged Business Enterprises (Dbe) For Highway Construction In Kentucky, Fy 2004 Update, Brad W. Rister, Raymond F. Werkmeister, Paul E. Toussaint

Kentucky Transportation Center Research Report

The Kentucky Transportation Center gathered the appropriate information, performed a series of computations and analyses, prepared the attached documentation, and makes the following recommendations to the Kentucky Transportation Cabinet for their DBE goal for Federal Fiscal year 2004 (October 1, 2003 - September 30, 2004).

KTC recommends an overall DBE goal of 9.26%, of which 1.931% is anticipated to be satisfied by race/gender neutral prime contracts, and the resultant 7.33% should established as race/gender conscious subcontracts. The overall DBE goal figures stated here addresses an adjustment of 1.326% for the positive historical goal variance observed for the past eight years.


Evaluation Of Non-Nuclear Density Gauges, David L. Allen, David B. Schultz Jr., David Allen Willett Aug 2003

Evaluation Of Non-Nuclear Density Gauges, David L. Allen, David B. Schultz Jr., David Allen Willett

Kentucky Transportation Center Research Report

For the past several decades, density of freshly laid hot mix asphalt (HMA) mats has been measured by contractors, consultants or governmental agencies using nuclear density gauges. However, use of these devices requires the user to maintain an inordinate amount of records on the use of the equipment. These requirements include calibration and recalibration records, certification records of the operators, records on radiation badges, and periodic testing of the operator’s badges for radiation exposure. In addition, there is always the concern about possible accidents with the gauges that might expose the radiation source to the operators or other bystanders. Because …


Lessons Learned System For Kentucky Transportation Projects, Paul M. Goodrum, Mohammed F. Yasin, Donn E. Hancher Aug 2003

Lessons Learned System For Kentucky Transportation Projects, Paul M. Goodrum, Mohammed F. Yasin, Donn E. Hancher

Kentucky Transportation Center Research Report

A system of collecting, archiving, and disseminating lessons learned is a critical component of experienced-based processes, such as the design and construction of roadway and bridges. This report examines the development of a centralized, web-based Lessons Learned System for the Kentucky Transportation Cabinet. The research developed a working prototype of a lessons learned system that functions off of centrally located databases making it easier to administer and update. The Lessons Learned System was designed to accept both text and attachments through file uploads while maintaining relationships between these items of information in terms of a lesson learned. The report describes …


The Use And Performance Of Geogrids In Kentucky, Aric Cowne, Richard Reitenour, David L. Allen, R. Clark Graves Aug 2003

The Use And Performance Of Geogrids In Kentucky, Aric Cowne, Richard Reitenour, David L. Allen, R. Clark Graves

Kentucky Transportation Center Research Report

This report will investigate the history and usage of geogrids, a subfamily of geosynthetics, in Kentucky. The American Society for Testing and Materials (ASTM - 1994) has defined a geosynthetic as a planar product manufactured from a polymeric material used with soil, rock, earth, or other geotechnical-related material as an integral part of a civil engineering project, structure, or system. Geogrids, geosynthetics primarily used for reinforcement, are formed by a regular network of tensile elements with apertures of sufficient size to interlock with surrounding fill material. Geogrids are used as reinforcement by adding tensile strength to a soil matrix, thereby …


2003 Safety Belt Usage Survey In Kentucky, Kenneth R. Agent, Eric R. Green Aug 2003

2003 Safety Belt Usage Survey In Kentucky, Kenneth R. Agent, Eric R. Green

Kentucky Transportation Center Research Report

The objective of this study was to establish 2003 safety belt and child safety seat usage rates in Kentucky. The 2003 su rvey continues to document the results after enactment of a statewide mandatory safety belt law in 1994 and safety belt enforcement campaign. Data were collect ed at 200 randomly selected sites spread across Kentucky. Data from the individual sites were combined into a statewide percentage considering roadway functional classification, geographic region, and vehicle miles traveled.

The data show that the usage rate in 2003 (65.5 percent) was higher than that in 2002 (62.0 percent). This compared to 61.9 …


Evaluation Of Kentucky’S “Buckle Up Kentucky: It’S The Law & It’S Enforced” Campaign, Kenneth R. Agent, Eric R. Green, Ronald E. Langley Aug 2003

Evaluation Of Kentucky’S “Buckle Up Kentucky: It’S The Law & It’S Enforced” Campaign, Kenneth R. Agent, Eric R. Green, Ronald E. Langley

Kentucky Transportation Center Research Report

The objective of this report was to document the results of the “Buckle Up Kentucky: It’s the Law & It’s Enforced” campaign in Kentucky. The campaign involved a combination of earned media, paid media, and enforcement. The earned media started about three weeks prior to Memorial Day 2003 and continued through the enforcement period. The paid media started about two weeks prior to Memorial Day. The enforcement period was a two-week period including the week before and the week of Memorial Day.

The evaluation of the campaign included documenting the activities associated with the program (publicity and enforcement) and evaluating …


Crash Rates At Intersections, Eric R. Green, Kenneth R. Agent Aug 2003

Crash Rates At Intersections, Eric R. Green, Kenneth R. Agent

Kentucky Transportation Center Research Report

The objectives of this study were to develop a database of intersections, match traffic crashes to these intersections, calculate crash rates for various types of intersections, and identify intersections with the highest crash rates. A procedure was used to: a) identify intersections, b) assign crashes to these intersections, c) determine entering traffic volume, d) calculate a crash rate for each intersection, and e) calculate a critical rate factor (CRF) for each intersection.

About 7,000 intersections were identified with almost 19,000 crashes related to these intersections for the three-year period of 2000 through 2002. The analysis identified 428 intersections that had …


Polymethylmethacrylate Augmented With Carbon Nanotubes, David A. Pienkowski, Rodney J. Andrews Jul 2003

Polymethylmethacrylate Augmented With Carbon Nanotubes, David A. Pienkowski, Rodney J. Andrews

Center for Applied Energy Research Faculty Patents

An augmented synthetic resin is provided. That resin includes carbon nanotubes dispersed in a polymethylmethacrylate matrix. The method of preparing this synthetic resin includes the mixing and disaggregating of the carbon nanotubes.


A.M.I.S. And The Partitioning Of Preference, Ted H. Grossardt Jul 2003

A.M.I.S. And The Partitioning Of Preference, Ted H. Grossardt

Kentucky Transportation Center Presentations

This presentation reviews work by the researchers that combines group dialogic techniques with analytic hierarchy and GIS to bring the knowledge of large groups of people to bear on a highway routing problem. A significant question is how technical knowledge and local information can be combined, either dialogically or mathematically, to provide the most faithful and practical version of a collaborative preference surface, what we call the Analytic Minimum Impedance Surface, or AMIS. While all preferences can be summed directly for this purpose, it may be more accurate and effective to partition the preference contribution to the landscape by knowledge …


Constructibility Issues On Kytc Projects, Donn E. Hancher, Joseph J. Thozhal, Paul M. Goodrum Jul 2003

Constructibility Issues On Kytc Projects, Donn E. Hancher, Joseph J. Thozhal, Paul M. Goodrum

Kentucky Transportation Center Research Report

Constructibility is defined by the American Association of State Highway and Transportation Officials Subcommittee on Construction as “a process that utilizes construction personnel with extensive construction knowledge early in the design stages of projects to ensure that the projects are buildable, while also being cost-effective, biddable, and maintainable” A successful constructibility review process for a transportation agency must follow an established methodology similar to value engineering. The process must be flexible and address the critical issues impacting transportation construction projects, such as ease of construction, environmental factors, construction phasing and scheduling, project safety, and accommodation of future maintenance and operations. …


Reinforcement Alternatives For Concrete Bridge Decks, Chris Hill, Choo Ching Chiaw, Issam E. Harik Jul 2003

Reinforcement Alternatives For Concrete Bridge Decks, Chris Hill, Choo Ching Chiaw, Issam E. Harik

Kentucky Transportation Center Research Report

This report investigates the application of various reinforcement types in concrete bridge decks as potential replacements or supplements to conventional steel reinforcement. Traditional epoxy coated reinforcement (ECS), stainless steel clad (SSC) reinforcement, MMFX microcomposite reinforcement, and carbon fiber reinforced polymer (CFRP) reinforcement were evaluated. Tests were conducted to determine the material properties of each reinforcement type. Full-scale two-span reinforced concrete deck specimens were load tested to evaluate their performance. CFRP reinforcement was deployed in a single-span bridge located on Elkin Station Road in Clark County, KY. The SSC and MMFX reinforcements were each placed in a separate span in a …


Survey Of Welding Processes, Theodore Hopwood Ii Jul 2003

Survey Of Welding Processes, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

The current KYTC “SPECIAL PROVISION NO. 4 WELDING STEEL BRIDGES” prohibits the use of welding processes other than shielded metal arc welding (SMAW) and submerged arc welding (SAW). Nationally, bridge welding is codified under ANSI/AASHTO/AWS D1.5M/D1.5:2002 Bridge Welding Code. That document allows the use of other welding processes including flux core arc welding, gas metal arc welding, electroslag welding and electrogas welding after passing qualification tests.

Both the KYTC Special Provision and the Bridge Welding Code were reviewed. Representatives from 14 state highway agencies, fabrication shops, universities and welding equipment firms were questioned regarding the wider use of the welding …


Highway Crash Site Management, Monica L. Barrett, Jennifer R. Walton Jul 2003

Highway Crash Site Management, Monica L. Barrett, Jennifer R. Walton

Kentucky Transportation Center Research Report

Traveler delay is the problem most often associated with highway crashes, but by far the most serious problem is the resulting secondary crashes that occur. Another related issue is the danger posed to response personnel serving the public at the scene of a crash. The longer a crash is in place, the longer the responders are vulnerable and exposed to injury.

The Kentucky Transportation Center, in cooperation with the Kentucky Transportation Cabinet, developed a checklist and interagency workshop to address ways to secure and coordinate the resources necessary to restore the roadway’s operation in a safe and timely manner. The …


Abandoned Railroad Corridors In Kentucky: An Inventory And Assessment, Lisa Rainey Brownell, Kentucky Transportation Center Jun 2003

Abandoned Railroad Corridors In Kentucky: An Inventory And Assessment, Lisa Rainey Brownell, Kentucky Transportation Center

Kentucky Transportation Center Research Report

This report provides an inventory of Kentucky's abandoned rail lines and a detailed assessment to highlight the lines that may be the most suitable for future trail use. A secondary purpose of the report was to inventory historic railroad structures. Over 125 different abandoned rail lines were identified, mapped using GIS technology, and assessed for their current use and condition. These abandoned rights of way exist in all regions of the state, in urban and rural areas.


Development Of Procedures For Identifying High-Crash Locations And Prioritizing Safety Improvements, Kenneth R. Agent, Lenahan O'Connell, Eric R. Green, Doug Kreis, Jerry G. Pigman, Neil Tollner, Eric C. Thompson Jun 2003

Development Of Procedures For Identifying High-Crash Locations And Prioritizing Safety Improvements, Kenneth R. Agent, Lenahan O'Connell, Eric R. Green, Doug Kreis, Jerry G. Pigman, Neil Tollner, Eric C. Thompson

Kentucky Transportation Center Research Report

The objectives of this study were to review and analyze the current procedures for identifying high-crash locations and evaluating and prioritizing roadway safety improvements at high-crash locations, and to recommend improved methods. Several tasks were undertaken to accomplish these objectives, including the following:

  • Review of program guidelines and procedures used by other states to prioritize improvements at high-crash locations
  • Review and documentation of Kentucky’s current procedures
  • Update of Kentucky’s Crash Buildup Program software to be compatible with the 2000 crash report form
  • Development of new software to assist in estimating the benefits and costs of potential projects for inclusion in …


Intelligent Transportation Systems Statewide Architecture, Joseph D. Crabtree, Jennifer R. Walton Jun 2003

Intelligent Transportation Systems Statewide Architecture, Joseph D. Crabtree, Jennifer R. Walton

Kentucky Transportation Center Research Report

This report describes the development of Kentucky’s Statewide Intelligent Transportation Systems (ITS) Architecture. The process began with the development of an ITS Strategic Plan in 1997-2000. A Business Plan, developed in 2000-2001, translated the goals of the Strategic Plan into specific project recommendations. To develop the Statewide Architecture, the project team first inventoried all existing and planned ITS projects in the state. A project architecture was developed for each identified project, and these project architectures were then merged to form the Statewide Architecture. This report describes the background work that set the stage for the architecture, the actual architecture development …


Assessment And Modeling Of Stream Mitigation Procedures [2003], Bernadette S. Dupont, Sudhir Palle May 2003

Assessment And Modeling Of Stream Mitigation Procedures [2003], Bernadette S. Dupont, Sudhir Palle

Kentucky Transportation Center Research Report

As population increases, so does the need to improve and augment the road network. Construction of new roadways or modification of existing roads often requires diversion or modification of streams. If a stream is disturbed, government regulations require mitigation or compensatory replacement of the affected area in a similar environment. Stream mitigation is of particular importance in Kentucky, as Kentucky ranks second in the United States for having the most miles of waterways. Consequently, stream mitigation has become a significant factor in roadway construction costs. To date, no studies have been made to assess the execution of the mitigation plans …


Assessing The Benefits Of Misting–Cooling Systems For Growing/Finishing Swine As Affected By Environment And Pig Placement Date, Thomas C. Bridges, Larry W. Turner, Richard S. Gates, Douglas G. Overhults May 2003

Assessing The Benefits Of Misting–Cooling Systems For Growing/Finishing Swine As Affected By Environment And Pig Placement Date, Thomas C. Bridges, Larry W. Turner, Richard S. Gates, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

The NCPIG swine growth model was used to evaluate swine growth performance for Wilmington, North Carolina; Bardstown and Mayfield, Kentucky; and Oklahoma City, Oklahoma as influenced by the use of a misting–cooling system. Five pig placement dates (Julian days 106, 126, 146, 166, and 186) were evaluated for each location using 22 years of weather data (1978–1999). The use of a misting system, while quite variable, was found to be generally profitable, reducing the length of the time to reach market weight. As the placement date increased, the average return to misting ($/pig/year) decreased from $8.12 to $1.98 for Oklahoma …


Developing The Next Generation Of Technological Aids To Effective Public Involvement In Public Transportation Planning & Design, C. Anneta Arno Anneta, Keiron Bailey, Ted H. Grossardt May 2003

Developing The Next Generation Of Technological Aids To Effective Public Involvement In Public Transportation Planning & Design, C. Anneta Arno Anneta, Keiron Bailey, Ted H. Grossardt

Kentucky Transportation Center Faculty and Researcher Publications

Problem

Public involvement in the design of complex public infrastructure solutions, such as a new light rail line, including stops, stations and transit centers, and associated Transit- Oriented Developments (TOD), often relies on lengthy public meetings during which the complexities and subtleties of design preferences, their articulation and communication is overwhelming to both participants and design professionals. Such gatherings can produce more confusion than clarity for the public and design professional alike, especially when strong personalities highlight differences and discourage compromise and consensus. More effective methods of discerning, developing and evaluating the nature of the public’s different preferences and perspectives, …


Roadway Lighting And Driver Safety, Eric R. Green, Kenneth R. Agent, Monica L. Barrett, Jerry G. Pigman May 2003

Roadway Lighting And Driver Safety, Eric R. Green, Kenneth R. Agent, Monica L. Barrett, Jerry G. Pigman

Kentucky Transportation Center Research Report

The objectives of this project were to: a) analyze the safety benefits associated with roadway lighting; b) determine the design of the lighting installation necessary to provide an adequate level of lighting; c) investigate how lighting affects the driver and the roadway’s surrounding environment; d) review the economic correlation between effective lighting and cost savings for the State; e) provide input for updating the current section on street and highway lighting in the Traffic Guidance Manual; and f) analyze crash data to identify nighttime high crash locations. The procedure involved a literature search, a survey of states, crash data analysis, …


Method Of Preparing A Composite Polymer And Silica-Based Membrane, Dibakar Bhattacharyya, Stephen M. Ritchie, Leonidas G. Bachas, Jamie A. Hestekin, Subhas K. Sikdar Apr 2003

Method Of Preparing A Composite Polymer And Silica-Based Membrane, Dibakar Bhattacharyya, Stephen M. Ritchie, Leonidas G. Bachas, Jamie A. Hestekin, Subhas K. Sikdar

Chemical and Materials Engineering Faculty Patents

A method for preparing a chemically activated or polyamino acid functionalized membrane includes the steps of permeating a silica-based membrane with a solution of silane and a solvent so as to react methoxy groups of the silane with silanol groups of the membrane to incorporate epoxide groups and attaching a polyamino acid to the membrane by reacting a terminal amine group of the polyamino acid with one of the epoxide groups on the membrane.


Preparing And Regenerating A Composite Polymer And Silica-Based Membrane, Dibakar Bhattacharyya, Stephen M. Ritchie, Leonidas G. Bachas, Jamie A. Hestekin, Subhas K. Sikdar Apr 2003

Preparing And Regenerating A Composite Polymer And Silica-Based Membrane, Dibakar Bhattacharyya, Stephen M. Ritchie, Leonidas G. Bachas, Jamie A. Hestekin, Subhas K. Sikdar

Chemical and Materials Engineering Faculty Patents

A method for preparing and regenerating a chemically activated or polyamino acid functionalized membrane includes the steps of permeating the silica-based membrane with a solution of silane and a solvent so as to react methoxy groups of the silane with silanol groups of the membrane to incorporate epoxide groups and attaching a polyamino acid to the membrane by reacting a terminal amine group of the polyamino acid with one of the epoxide groups on the membrane. The membrane is regenerated after metal entrapment by utilizing helix-coil properties of polyamino acids.


Traffic Control At Stop Sign Approaches, Kenneth R. Agent Apr 2003

Traffic Control At Stop Sign Approaches, Kenneth R. Agent

Kentucky Transportation Center Research Report

The objectives of this report were to: a) determine the number of crashes in Kentucky involving a driver disregarding a stop sign and the locations where these occur, b) determine the characteristics of these crashes, c) investigate loca tions with a large number of this type of crash, and d) make recommendations to reduce the probability of a driver disregarding a stop sign. The majority of the analyses involved a review and analysis of crashes where a stop sign was listed as the traffic control and “disregarding the tra ffic control” was listed as a contributing factor. Intersections having a …


Harvesting, Drying, And Storing Grain Sorghum, Samuel G. Mcneill, Michael D. Montross Apr 2003

Harvesting, Drying, And Storing Grain Sorghum, Samuel G. Mcneill, Michael D. Montross

Agricultural Engineering Extension Publications

Grain sorghum (milo) has been successfully produced in many areas of Kentucky and can be grown in alternating years with soybeans to replace corn in a crop rotation cycle. For most of the past 20 years, it has ranked fourth in production of all grain crops grown in the state and was valued at $1.16 and $1.53 million in 1999 and 2000, respectively. Rotating milo with soybeans can help control soybean cyst nematodes and other pests that suppress yield. It can provide higher yields than corn in dry years, especially on sandy soils. The feed/energy value of milo is similar …


Structural Evaluation Of The Historic John A. Roebling Suspension Bridge, Wei-Xin Ren, Issam E. Harik, George E. Blandford, Michael Lenett, T. Michael Baseheart Apr 2003

Structural Evaluation Of The Historic John A. Roebling Suspension Bridge, Wei-Xin Ren, Issam E. Harik, George E. Blandford, Michael Lenett, T. Michael Baseheart

Kentucky Transportation Center Research Report

The John A. Roebling suspension bridge, formerly the Covington-Cincinnati suspension bridge over the Ohio River was completed in 1867 and is still serving the Northern Kentucky community. The objective of this study is to assess the bridge load capacity via the dynamics-based technique. The scope of research includes finite element modeling and modal analysis, field ambient vibration testing, finite element model calibration to field test results, and bridge load-capacity evaluation. It is demonstrated that stress stiffening of cable elements plays an important role in both static and dynamic analyses of the Roebling suspension bridge. Large deflection behavior has been shown …