Engineering Commons^™

Effects Of Load Distributions And Axle And Tire Configurations On Pavement Fatigue, Herbert F. Southgate, Robert C. Deen

Kentucky Transportation Center Research Report

Damage factor relationships for axle and tire configurations are presented. Adjustment factors are provided to account for variations in load distributions within axle groups, distances between axles of a tandem, and variations in tire pressure for both dual and flotation tires.

Properly accounting for accumulated fatigue of a pavement requires a traffic volume, proportions of vehicle styles (classifications) within the of service, estimate of the average damage factor for each classification, reasonable measure of traffic stream, dates and estimates of tire contact pressures.

All adjustment factors presented are based on analyses of a limited number of structures and should be …

Use Of Nondestructive Testing To Prevent Failures Of In-Service Metal Bridges, Theodore Hopwood Ii, Robert C. Deen

Kentucky Transportation Center Research Report

The failure of metal bridges, subject to in-service fracture problems mainly caused by fatigue, may be prevented or minimized by performance of periodic nondestructive testing. Attendant factors that justify funding for such inspections include the potential for bridge failure, the consequences of bridge collapse, risk analyses, and inspection strategies. Factors that affect structural integrity include structural design, construction quality, and service loadings.

Details of a computer/strain-gage system capable of obtaining strain-gage data from critical structural elements are described. Data are processed to determine the stress-range distribution, number of stress cycles, resolved mean stress range, need for structural inspection, critical crack …

Documentation For 1986 Weight-Distance Tax Analyses Using Lotus 1-2-3, Herbert F. Southgate

Kentucky Transportation Center Research Report

No abstract provided.

Evaluation Of A Full-Depth Asphaltic Concrete Pavement, Herbert F. Southgate, Gary W. Sharpe, Mark Anderson

Kentucky Transportation Center Research Report

This study was initiated to verify a newly-developed set of design curves for full-depth asphaltic concrete pavements. Quality control during construction was checked using nuclear density testers, Benkelman beams, and a Road Rater. During the course of this study, an analysis system (predicated upon the elastic theory model) was developed to interpret the dynamic deflections as measured by the Road Rater. The thickness design curves were verified by elastic theory and deflection testing within the accuracy of construction variations.

Measured rut depths were analyzed in terms of potential rut depth resulting from consolidation under traffic due to lack of obtaining …

Nondestructive Evaluation Of Rigid Pavements Using Road Rater Deflections [1986], Gary W. Sharpe, Mark Anderson, Robert C. Deen, Herbert F. Southgate

Kentucky Transportation Center Research Report

Dynamic deflections have been used to determine in-place structural conditions of rigid pavements, based on modifications of principles and experience with the structural evaluation of flexible pavements. Details of the use of elastic layer theory to simulate deflection measurements associated with loadings for the Kentucky Road Rater are presented. Included is an illustration of the use of field deflection measurements to "back calculate" in-place moduli. The procedures are generally iterative and involve matching measured deflections with theoretical deflections. Elastic layer principles have been used to simulate deflections only at the mid slab position. Relationships regarding deflections at other locations on …

Stability Of Embankments On Clay Foundations, Tommy C. Hopkins

Kentucky Transportation Center Research Report

Ninety-one well-documented geotechnical failures are reviewed. The case studies involved the failure of embankments, footings and load tests, excavated slopes, and natural slopes. Seventy-five of the geotechnical failures had been analyzed using total stress analysis. Sixteen of the case failures had been analyzed using effective stress analysis. Based on a review of these case studies, there are discrepancies between predicted and actual stabilities of geotechnical structures and there is a tendency tu overestimate the factor of safety. Differences that may arise between predicted and actual performances are discussed and examined and guidelines are proposed for evaluating the potential of successfully …

Use Of Post Delineators On Interstates, Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

The objectives of this report were to investigate 1) the potential benefits of using flexible posts for post delineators and 2) the possibility of not requiring post delineators on sections of interstate-type highways where recessed markers are installed.

It is recommended that post delineators should only be used when the design curvature is 1.5 degrees or more, and the spacing should be based on the formula given in Table III – 1 of the MUTCD. Data obtained concerning the performance of flexible posts do not support widespread use at this time. A testing program should be developed to obtain an …

Treatment Of Narrow Medians On Four-Lane Rural Roadways, Jerry G. Pigman, Kenneth R. Agent

Kentucky Transportation Center Research Report

The objective of this study was to investigate alternatives to paved mountable medians that have been used in the past on sections of four-lane, partially controlled access roads where right-of-way is restricted. These mountable medians present obvious operational problems due to the 3-inch difference in height as compared to the through lanes. In addition, construction and maintenance problems are associated with mountable medians because of the height differential.

A telephone survey of 16 states was conducted to determine their policy for separation of rural four-lane roads with partial control of access and narrow medians. Accident analyses comparing roads in Kentucky …

Traction Characteristics Of Prepared Traffic Lanes, Eddie C. Burt, James H. Taylor, Larry G. Wells

Biosystems and Agricultural Engineering Faculty Publications

Traction characteristics of lugged and smooth tires were compared on prepared traffic lanes and on conventional seedbed conditions. Results indicated that elevated traffic lanes offer important traction advantages over seedbeds in wet soil conditions. In dry soil conditions, traction on elevated traffic lanes was sometimes less than on the seedbed conditions. A timeliness advantage in mobility for the elevated traffic lanes was found to be up to 2 days in extremely wet conditions. A non-elevated traffic lane showed no traction advantage in wet conditions.

Delineation Of Horizontal Curves, Kenneth R. Agent, Tom Creasey

Kentucky Transportation Center Research Report

The objective of this study was to investigate the ability of various traffic control measures to delineate horizontal curves so drivers would perceive the curve and slow to an appropriate speed and then be provided guidance through the curve. Pavement delineation (raised pavement markers, transverse stripes, or rumble strips) and shoulder delineation (post delineators and chevron signs) were used. A laboratory test found that a post delineator configuration in which the distance from the post to the pavement edge and the post spacing remained constant while the height of the delineator on the post increased made a curve appear sharper …

Transplanter Mounting Attachment For A Harvester, Larry D. Swetnam, James H. Casada, Linus R. Walton

Biosystems and Agricultural Engineering Faculty Patents

A transplanter mounting attachment for attachment to a crop harvester including a pivot shaft operatively connected for rotation about an axis extending longitudinally with respect to a support frame of a crop harvester. A rotating sleeve substantially orthogonally disposed with respect to the pivot shaft and rotatably mounted relative thereto. A connecting shaft substantially orthogonally disposed with respect to the pivot shaft and rotatably mounted relative thereto. At least one transplanter attaching assembly operatively connected to the rotating sleeve and being raised or lowered upon rotary motion being imparted to the rotating sleeve. Wheels are provided which are operatively connected …

Home Water Testing, Joseph L. Taraba, Tom Ilvento, Linda Heaton, Bob Herbst, Grant Thomas, Dwight Crum

Agricultural Engineering Extension Updates

Routine testing for a few of the most common contaminants is highly recommended. Even if you currently have a safe, pure water supply, regular testing can be valuable because it establishes a record of water quality. This record can be helpful in solving any future problems and in obtaining compensation if someone damages your water supply. Testing needs to be performed by certified testing laboratory using USEPA methods of collection, storage and testing. Unbiased testing needs to be established and has more validity in court proceedings to establish responsibility.

Home Treatment Devices Listing Organizations, Joseph L. Taraba

Agricultural Engineering Extension Updates

Today there is a need for consumer information to assess the multitude of drinking water treatment devices for home use as well as related private drinking water services. There are several organizations that have conducted or conduct on a continuing basis testing of water treatment devices and water treatment services.

Certified Water Well Drillers, College Of Agriculture, University Of Kentucky

Agricultural Engineering Extension Updates

Kentucky statute and regulations now require water well drillers to be certified. Farmstead wells and stock wells are exempt except when a farmstead well is used for irrigation or domestic water supply. Since animal consumption wells are covered there is some confusion regarding stock wells. The Kentucky Division of Water strongly recommends that all wells, regardless of use, be drilled and constructed by a certified driller.

Traffic Accident Rates In Kentucky (1984), Kenneth R. Agent

Kentucky Transportation Center Research Report

Average accident rates, using 1984 accident data only as well as combined 1980 through 1984 data, were calculated for Kentucky highways. Comparison of 1984 to combined 1980 through 1983 rates show the rates have remained stable. There was an increase in total accidents and total accident rate in 1984 compared to 1980 through 1983 data while there was a decrease in the fatal accident rate. Several methods of classifying highways were used when calculating average rates. Those rates may be used in the high-accident location identification program. Average and critical numbers of accidents also were determined for use in the …

A Generalized Slope Stability Computer Program: User’S Guide For Hopk-I, Tommy C. Hopkins

Kentucky Transportation Center Research Report

Data entry and operation of a generalized slope stability computer program are described. The computer program is based on a new approach to formulating and solving the slope stability equilibrium equations. The moment equation as well as the horizontal and vertical equilibrium equations are considered in the model. The purpose of the study was to implement the new approach. The computer program may be used to compute the factor of safety of slip surfaces of arbitrary shape and circular slip surfaces. Effective stress and total stress conditions may be analyzed. Four options are available for computing pore pressures. Both piezometric …

Workshop On Roadway And Street Drainage, Ronald D. Hughes, David L. Allen

Kentucky Transportation Center Research Report

No abstract provided.

The Feasibility Of Draglines For Mine Reclamation, Mark Anderson

Kentucky Transportation Center Research Report

Draglines are presented in this paper as an alternative for mine reclamation in steep sloping areas. Some abandoned mines in steep sloping areas of Kentucky have unreclaimed slopes which pose safety problems, as well as environmental and aesthetic problems. In addition, many active mines in steep sloping areas of Kentucky have slopes which must be reclaimed in the near future. Current methods of slope reclamation in Kentucky typically involve traditional heavy equipment. The current methods are not cost efficient in some cases, and are not safe in some applications.

The paper includes a history of draglines. Early development is summarized, …

Estimation Of Equivalent Axleloads, John A. Deacon, Jerry G. Pigman, Jesse G. Mayes

Kentucky Transportation Center Research Report

The primary objective of this research study was to develop a procedure for estimating equivalent axle loads for purposes of flexible-pavement design. Maximum use was made of historical data and well-accepted procedures were used in developing the prediction model. A series of computer programs was developed to summarize truck-weight and classification data such that traffic characteristics could be estimated from a matrix of data classified by geographic area, Federal highway system, volume, and extent of coal haulage. An equation was developed with the following seven parameters as independent variables; 1) annual average daily traffic volume, 2) average fraction of trucks …

A Computerized Analysis Of Flexible Pavement Rutting Behavior (Pavrut), David L. Allen, Robert C. Deen

Kentucky Transportation Center Research Report

The behavior of asphalt-bound layers, unbound aggregate bases, and foundation soils (subgrades) may be affected by such variables as gradation, asphalt and (or) moisture contents, type of aggregate, density, method of compaction, temperature, magnitude and frequency of loading, duration of each load cycle, and other less significant variables. The complex interaction of all these variables yields a composite behavior for a particular pavement structure that could become manifest in some form of distress or even complete "failure."

Flexible pavements are susceptible to rutting. But it is not well known where and to what extent rutting takes place within a pavement …

Characterizing Soil Deformation By Direct Measurement Within The Profile, Randall K. Wood, Larry G. Wells

Biosystems and Agricultural Engineering Faculty Publications

A unique feature of the University of Kentucky soil bin enables deformation to be characterized by studying a cross-sectional soil profile grid pattern. Modular sections of the bin are laterally removed to expose the cross-section after passes of a pneumatic tire.

The measured displacements of the grid points were converted to values of volumetric strain and then compared to soil density as measured by a dual probe gamma-ray density gauge following tests at various soil conditions. Final soil bulk density determinations using the two methods were not statistically different..

Jefferson Freeway Investigation (Westbound Lanes), Herbert F. Southgate, Gary W. Sharpe, Theodore Hopwood Ii, James H. Havens, Mark Anderson, David Q. Hunsucker, Robert C. Deen

Kentucky Transportation Center Research Report

The Kentucky Transportation Research Program (KTRP) was retained to perform an investigation for the Kentucky Department of Highways to assess damage that may be attributed to passage of the Model 992C over portions of the Jefferson Freeway. KTRP investigators conducted visual surveys, performed Road Rater deflection tests, did in-place California Bearing Ratio (CBR) testing on subgrade materials, obtained pavement cores, and conducted laboratory tests and analyses.

It appeared the pavement was damaged by the front-end loader. No evidence of damage to the bridges attributable to the front-end loader was detected. Damage to the pavement attributable to passage of the front-end …

Evaluation Of Stone Column Stabilized Embankment Foundation, Bobby W. Meade, David L. Allen

Kentucky Transportation Center Research Report

The purpose of this study was to document construction procedures, monitor field performance, and make recommendations concerning the effectiveness and future use of a foundation improvement procedure using stone columns for stabilization. This effort was executed by use of field inspections and photographs, instrumentation to monitor foundation and field responses and laboratory analyses of existing and possible conditions.

Instrumentation included earth pressure meters, a multipoint settlement gage, a horizontal slope inclinometer, a settlement platform and vertical slope inclinometers. Settlement of the foundation after column construction was found to be approximately 8 inches as compared to a predicted total settlement of …

Suggested Changes To Kentucky Statutes (Vehicle Weights And Dimensions), Herbert F. Southgate, Robert C. Deen

Kentucky Transportation Center Research Report

The purposes of this report are: 1. To clearly define the terms ''tandem," "tridem," and “triaxle." 2. To clearly define the term "600 pounds per inch width of tire" as the "width of the tread in contact with the pavement." 3. To make the axle load limits the same throughout the statutes. 4. To suggest elimination of indentified discriminatory legislation. 5. To recommend additional legislation: a. to clearly define the purpose and use of "air-bag" suspension systems -- those that can be raised or lowered by the driver, and b. to enable vehicle weight enforcement officers to use shipping documents …

A Survey Of The States On Problems Related To Bridge Approaches, David L. Allen

Kentucky Transportation Center Research Report

A questionnaire was sent to the states concerning problems with bridge approaches. Seven questions were included in the survey, including questions on the use of integral end bents and spread footers. This report summarizes the responses. Appendix A contains the detailed responses received, and Appendix B contains specifications and standard drawings used by some of the states.

Impact Evaluation Of The Traffic Alcohol Program In Lexington, Kentucky, Jerry G. Pigman, Kenneth R. Agent

Kentucky Transportation Center Research Report

This report is an evaluation of increased police enforcement to reduce alcohol-related accidents in Lexington-Fayette County, Kentucky. Three types of data were coIlected as a means of evaluating the Traffic Alcohol Program; accident data, arrest and adjudication data, and cost-effectiveness data.

Results from before-and-after comparisons and time-series analysis show alcohol related accidents decreased significantly during the study period. When comparing two years before with three years during the increased enforcement, the percent reduction in alcohol-related accidents was 28.1 percent using standard before and after analysis and 29.1 percent using time-series analysis. During the same time period, alcohol related fatal or …

Cultivating Attachment For Crop Harvester Support Vehicle, Larry D. Swetnam, James H. Casada, Linus R. Walton

Biosystems and Agricultural Engineering Faculty Patents

A cultivator for attachment to a crop harvester including at least one tool frame member with soil tilling tools adjustably mounted relative thereto. A shaft is provided rotatably mounted relative to a support frame of the crop harvester. An actuating member is operatively connected to the shaft and the support frame for selectively imparting rotation to the shaft. A link is operatively, pivotally connected between the tool frame member and the support frame for guiding the frame member and the soil tilling tools between a raised position out of engagement with a ground surface and a lowered position into engagement …

Demonstration And Preliminary Evaluation Of The Acoustic Emission Weld Monitor, Theodore Hopwood Ii, Robert C. Deen

Kentucky Transportation Center Research Report

This report describes the demonstration and preliminary evaluation of the microprocessor-based acoustic emission weld monitor (AEWM) developed for the Federal Highway Administration by GARD Inc. of Niles, IL. The equipment was tested successfully on butt welds in several fabrication shops by the Kentucky Transportation Research Program (KTRP). Some problems were encountered in monitoring fillet welds.

The AEWM was demonstrated to personnel from 20 state agencies representing FHWA Regions 1, 3, 4, and 5. The demonstrations were performed at three different fabrication shops in Pennsylvania, Georgia, and Wisconsin.

A preliminary evaluation of the AEWM is included. Also, the summary of a …

Evaluation Of Construction Zone Pavement Marking Materials, Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

The objectives of this report were to evaluate all available foil-back and removable tapes as well as construction zone raised pavement markers and to recommend materials that should be included on approved lists for use by the Kentucky Department of Highways. The tapes were placed on transverse test sections and as lane lines and the reflectivity, durability, and appearance were observed. The markers were observed at test sections as well as at construction sites.

Lists of tapes to be included on the approved lists for foil-back and removable tapes were recommended. Tapes manufactured by 3M and Flex-0-Lite were included on …

Latex-Concrete Overlays On Bridge Decks (I64, Mp 150 To West Virginia Line), James H. Havens, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

Visual field inspections and soundings were performed on latex concrete overlays on 24 bridges on I 64 between Milepoint 150 and the West Virginia state line. The inspections were conducted in response to a request from the Kentucky Department of Highways to determine if cracking problems in the overlays were related to workmanship or materials.

The field inspections revealed that most of the overlay crack problems were related to 1) reflection cracking caused by pre-existing fractures in underlying concrete bridge decks and 2) “pull-in” cracks in the overlay, caused by belated tyning of the bridge deck.

Field diaries, inspection reports, …