Engineering Commons^™

Remedial Stability Analysis Of Unstable Eastern Approach Embankment, Bluegrass Parkway Bridges Over Chaplin River, Tommy C. Hopkins, S. M. Yoder

Kentucky Transportation Center Research Report

In a meeting held on March 7, 1973, the Division of Research was requested to perform a supplementary slope stability analysis of the unstable, eastern approach embankment and foundation located at the crossing of the Bluegrass Parkway over Chaplin River and extending between Stations 2317+14 and 2321+00. Previously (see referenced report), two remedial schemes had been considered for increasing the stability of the unstable soil mass to an acceptable level. Those included: 1) loading the toe area of the existing, eastern approach slope with a berm, including a sloping berm, and 2) unloading the upper portion of the eastern slope …

Vibratory Roller Evaluation, Donald C. Newberry Jr.

Kentucky Transportation Center Research Report

In a field evaluation of vibratory rollers, an end-result specification based on a statistical analysis of densities obtained on previous construction projects indicated 98 percent of laboratory density (Marshall) to be desired for Bituminous Concrete, Class I Base. The minimum average of 5 density tests was set at 96.4 percent. Conventional rollers, vibratory rollers, and combinations thereof were qualified on the basis of density-growth curves determined on one or more 1000-foot test sections. An overall average compaction of 97.8 percent of Marshall density was obtained on the Cumberland Parkway project. Similar controls initiated on the Green River Parkway project were …

A Survey Of Reflective Sheeting For Highway Signs, Rolands L. Rizenbergs

Kentucky Transportation Center Research Report

A questionnaire (see the APPENDIX) was sent to highway agencies in all 50 states, the District of Columbia and Puerto Rico for the purpose of surveying state practices in regard to reflective sheeting purchase, usage specifications, testing, etc. The response was 100 percent and, thus, demonstrated a high degree of interest in the subject.

Responses to the questionnaire are tabulated on the attached tables. An attempt was made to report answers provided by the agencies without interpretation except in a few isolated cases where the necessafy information was available to properly relate the response to a given question. In a …

Stability Of A Side-Hill Embankment, Tommy C. Hopkins, Harry F. Girdler, Steve M. Yoder

Kentucky Transportation Center Research Report

The report submitted herein is a case history describing observations and in-depth analyses made at a highway site involving a massive, unstable side-hill embankment located on I-64 in Boyd County. The in-depth study was initiated in January 1973. The I-64 site was selected for study because it contained several design, construction and maintenance features as well as soil types that are typical of many highway embankments in Kentucky. Side-hill fill situations are common design problems and oftentimes have required extensive maintenance after construction. Major objectives of the study were to 1) determine the causes of instability of the I-64 embankment, …

Fatigue Analysis Of Central Bridge Deduced From Strain Gage Data And Probability Analysis, R. J. Bruner Iii

Kentucky Transportation Center Research Report

This report presents evaluations of the load history of the Central Bridge from both strain gage data and probability analysis. Estimation of remaining service life is made through fatigue criteria. Also included is a comparison (from strain gage data) of live load stresses carried by parallel eye bars. An appendix provides a user's manual for the computer program for probability-based analyses of load events and fatigue-life computations.

Establishment And Maintenance Of Roadside Plantings And Turf, Kenneth N. Franks

Kentucky Transportation Center Research Report

A series of experimental investigations initiated by the Kentucky Highway Department over a six-year period were designed for the purpose of studying the I adaptability, establishment, and maintenance of roadside plantings and turf, including the stabilization and management of roadside soils.

Experimental Installations Of Impact-Attenuating Devices, Jerry G. Pigman, William M. Seymour, Don L. Cornette

Kentucky Transportation Center Research Report

From a survey of the interstate system in Kentucky, 26 gore sites were found to be eligible for safety improvements. Energy absorbing barriers have been installed at five. Barriers are planned at 11 sites; seven sites have been contour graded; and three sites have been dismissed from consideration.

HI-DRO Cushions and Fitch Inertial Barriers were found to be effective crash cushions. HI-DRO Cushion maintenance costs per impact were less than those for Fitch Inertial Barriers; however, initial costs of materials and installation were higher. The HI-DRO Cushion is generally more adaptable to narrow and relatively short areas than either the …

Slope Stability Analysis: A Computerized Solution Of Bishop’S Simplified Method Of Slices, Steve M. Yoder, Tommy C. Hopkins

Kentucky Transportation Center Research Report

A computer program based on Bishop's simplified method of slices (1954) and capable of analyzing the slope stability of a multilayered soil mass is described. The computer program was specifically developed for analyzing the slope stability of highway bridge approach embankments; however, it can be applied to a broad spectrum of practical slope configurations and bearing capacity problems. Details of the use, applications, and accuracy of the program are presented. Important features of the computer program include a grid type, search operation for locating the critical shear surface and a ledger printout of the forces acting on each individual slice. …

Evaluation Of The High-Accident Location Spot-Improvement Program In Kentucky, Kenneth R. Agent

Kentucky Transportation Center Research Report

The purpose of this study was to determine the overall effectiveness of the spot-improvement program in Kentucky. Safety improvements have been made at 349 locations (through June 30, 1971) since the program started in 1968. Before-and-after accident summaries were made at these locations as well as locations where the investigation resulted in no recommendations for improvements. It was found that the second-year before accident data was more representative of long-term accident experience than the first-year before data. From the analyses, it was found that the spot-improvement program has resulted in a significant reduction in accidents at high-accident location sites. The …

Settlement Of Highway Bridge Approaches And Embankment Foundations, Bluegrass Parkway Bridges Over Chaplin River, Tommy C. Hopkins

Kentucky Transportation Center Research Report

The report examines the cause of a differential settlement between the highway approach embankments and bridge decks and abutment tilting at a bridge site located on the Bluegrass Parkway in Kentucky. The site contains several design, construction and maintenance features and soil types that are typical of many bridge sites in Kentucky. The approach embankments are side-hill fills. The approach pavements have settled several inches and have been patched on numerous occasions. Each of the four abutments give the appearance of having tilted backward toward the backfill. However, closer examination shows that the abutments have moved laterally toward the bridge …

Annals Of The Research Division, Robert C. Deen

Kentucky Transportation Center Research Report

No abstract provided.

Before-And-After Analysis Of Safety Improvements On I 75 In Northern Kentucky, Jerry G. Pigman, Don L. Cornette

Kentucky Transportation Center Research Report

In an attempt to evaluate the effectiveness of various safety improvements on approximately five miles of I 75 in northern Kentucky, a before-and-after analysis of accidents was conducted. Safety improvements were: 1) a variable message signing system in the northbound direction; 2) a New Jersey-type median barrier wall; and 3) general improvements such as guardrail end treatments, break-away sign installations, contour grading, etc.

Results indicate the safety improvements were effective in reducing the overall accident rate. Separate analysis also revealed that variable message signs were effective in bringing about a significant reduction in accident rates. There were no fatalities during …

Kentucky Cbr’S And The Soil Support Value, Tommy C. Hopkins, Robert C. Deen

Kentucky Transportation Center Research Report

Several ASTM and Kentucky CBR tests were performed at different molding moisture contents and compactive energies on the AASHO embankment soil, four representative Kentucky soils, and one soil from Ohio. These data were compared to CBR data previously reported by Shook and Fang. For CBR's ranging from about 4 to 12, a relationship was developed between Kentucky and ASTM CBR's. Within this range, Kentucky and ASTM CBR's are approximately equal. Molding specimens under the static pressure of 2000 pounds per square inch as used in the Kentucky CBR procedure produced specimens with initial dry densities that averaged about 6 percent …

Models Of Outdoor Recreational Travel, John A. Deacon, Jerry G. Pigman, Kenneth D. Kaltenbach, Robert C. Deen

Kentucky Transportation Center Research Report

The purpose of this investigation was to evaluate models of travel flow from population centers throughout the United States to outdoor recreational areas in Kentucky. Data were obtained by means of a license-plate, origin-destination survey at 160 sites within 42 recreational areas and by means of a continuous vehicle counting program at eight of these sites. Attempts to simulate distributed travel flows concentrated on various single-equation models, a cross-classification model, and gravity and intervening opportunities models. The cross-classification model was found to be an acceptable means for simulating and predicting outdoor recreational travel flows and was decidedly superior to the …

The Safety Barrier Dilemma, James H. Havens, Don L. Cornette, William M. Seymour

Kentucky Transportation Center Research Report

"Ran-off-the-road" fatal accidents currently account for approximately 65 percent of all freeway fatalities (1). Accordingly, ever-increasing emphasis has been given to the development of effective safety barrier systems, from guardrails to earth berms to median barriers to energy absorbing barriers and mires. However, highway designers have also recognized that safety barriers are hazards in themselves, misfits in the highway environment, and that they are items to be eliminated wherever possible. In a study of fatal accidents on the Interstate Highway System, it was found that fixed object collisions have been the leading source of fatalities, accounting for 43 percent …

Characteristics Of Outdoor Recreational Travel, Jerry G. Pigman, John A. Deacon, Robert C. Deen

Kentucky Transportation Center Research Report

The purpose of this investigation was to examine the characteristics of travel to outdoor recreational areas in Kentucky. Data were obtained by means of a license-plate, origin-destination survey at 160 sites within 42 recreational areas and by means of a continuous vehicle counting program at eight of these sites. A computer algorithm was developed for error detection and subsequent adjustment of the volume data as necessitated by occasional malfunction of the traffic recorders and vandalism. Vehicle occupancy was found to depend of the type of recreational area, distance traveled, and vehicle type. Occupancy increased with increasing distance and was greatest …

Elements Of Median Design In Relation To Accident Occurrence, Gordon R. Garner, Robert C. Deen

Kentucky Transportation Center Research Report

The purpose of this study was to compare the accident histories of different median types and to provide verification of generally recommended median widths and slopes. A major limitation of the analyses was the small number of possible combinations of median width and cross slope available for study.

The analyses reported provided evidence from accident histories to support the general requirement that wider medians are safer medians. It was indicated that medians should be a minimum of 30-40 feet wide for high speed facilities and that flat slopes should be provided; 4:1 slopes are inadequate for medians less than 60 …

Tar Concrete Pavement Construction And Performance, Jerry G. Rose

Kentucky Transportation Center Research Report

In 1969, a 6.6-mile section of relocated KY 15 in Perry and Knott Counties was paved utilizing coal-tar (RT-12) concrete base and surface. This project was authorized under the Appalachian Regional Development Act of 1965 and was designated as experimental as a means of implementing a section of the Act.

Two nearby sections of KY 15, containing asphalt (PAC-5) concrete base and surface, were designated as control sections and used for comparison purposes. With the exception of the bituminous material, the experimental and control sections were purposefully made equal in all other respects. A design soil CBR of 9 was …

A Pavement Design Schema, James H. Havens, Robert C. Deen, Herbert F. Southgate

Kentucky Transportation Center Research Report

Elastic theory and 40 years of empirical flexible pavement design in Kentucky have been joined into the design system presented herein. A brief discussion is presented of the coupling mechanisms relating experience to theoretical analyses. An annotated design procedure is presented as a guide for pavement designers. Design nomographs account for a wide range of input parameters and permit the designer a wide choice of alternative thickness designs.

Mercury-Filled Settlement Gage, Tommy C. Hopkins, Robert C. Deen

Kentucky Transportation Center Research Report

A description is given of a remote sensing, multiple-point, mercury-filled settlement gage designed for measuring in-place settlements. The gage consists of settlement units positioned at locations where settlement measurements are desired and a monitoring unit located outside of construction limits. Settlement readings are observed on a mercury manometer located at the monitoring site and are· equal to the differences in initial and subsequent pressure head readings. Comparisons of measurements obtained at a highway construction site from mercury gage settlement units and conventional settlement platforms are presented and show very good agreement. With the mercury gage, a large amount of settlement …

Spraygrip Anti-Skid Treatments, Kentucky Turnpike, Jerry G. Rose

Kentucky Transportation Center Research Report

No abstract provided.

Energy Absorption Devices, James H. Havens

Kentucky Transportation Center Research Report

An ironic consequence of modern highways has been the emergence of new types of accidents. Recent investigations (1) have shown that "running off the road" may be the largest, single cause of fatalities on limited access, multilane roads. According to the 1967 Report of the Special AASHO Traffic Safety Committee ("Yellow Book") (2) the rate of accidents in gore areas is approximately four times that of ran-off-the-road accidents at other locations. Gore areas which are not or cannot be modified to provide favorable terrain and unobstructed recovery zones have been recognized as misfits in the environs of the highway. Crash …

Accidents On Rural Interstate And Parkway Roads And Their Relation To Pavement Friction, Cass T. Napier

Kentucky Transportation Center Research Report

Friction measurements were made with a skid trailer at 70 mph on 820 miles of rural, four-lane, controlled-access routes on the interstate and parkway systems in Kentucky. These facilities were subdivided into test sections and half-mile sites. Accident experience, friction measurements and traffic volumes were obtained for each subdivision.

The expression of accident occurrence which correlated best with skid resistance was wet-surface accidents per 100 million vehicle miles. There was a definite trend exhibiting a rapid decrease of accidents with increasing Skid Number (70 mph) to 26 ± 1; thereafter, with increasing Skid Numbers, the rate of decrease was considerably …

Accident And Economic Analyses Of Access Control On Several Bypasses, Kenneth R. Agent

Kentucky Transportation Center Research Report

In an effort to relieve congestion on urban streets, bypasses have been built to provide through traffic a route by which the downtown areas can be avoided.

In many cases, though, bypasses have created a serious accident potential because they were built with at-grade intersections and no access control. This leads to commercial developments along the bypass and congestion at major intersections. Bypasses were constructed in this manner because of the high initial cost involved in building a bypass with access control and grade-separated interchanges. There is, therefore, a need to determine if the accident cost savings, along with time …

A Rheological Study Of Cohesive Soils, David L. Allen

Kentucky Transportation Center Research Report

An attempt has been made to describe the mechanistic behavior of remolded and undisturbed soils by application of the principles of rheology. This was accomplished by approximating and comparing the data obtained from transient creep tests and relaxation tests to the mathematical behavior of mechanical impedance models. The data were also analyzed by transforming static moduli and compliances into dynamic values by the application of Fourier transforms. Distribution functions of relaxation and retardation times, obtained by the application of LaPlace transforms, are presented.

All soils tested exhibited similar dynamic moduli and complince curves indicating that soil type had little effect …

Construction Of Full-Depth Asphaltic Concrete Pavements, Jerry D. Ross, Herbert F. Southgate

Kentucky Transportation Center Research Report

Considerable attention has been devoted to the design and use of full-depth asphaltic concrete pavements. An experimental full-depth pavement was constructed on the Cannonsburg-Ashland Road (US 60), and the mechanical response of each asphaltic concrete layer to static and dynamic loading has been tested during construction.

This report is a documentation of section designs and construction procedures and summarily presents construction test results to be used in future analyses.

Rural Recreational Travel In Kentucky, Jerry G. Pigman

Kentucky Transportation Center Research Report

The purpose of this study was to develop a methodology for predicting travel patterns on routes leading to outdoor recreational areas in Kentucky. Data were collected by means of a license-plate, origin-destination survey at 160 sites within 42 recreational areas and by means of a continuous vehicle counting program at eight of these sites. Results indicate that the method of associating similar facilities is a reliable procedure for predicting traffic characteristics. Vehicle occupancy was found to depend on the type of recreational area, distance traveled, and vehicle type. Percentages of various vehicle types were also influenced by the type of …

Skid Resistance Of Pavements [Sept. 1972], Rolands L. Rizenbergs, James L. Burchett, Cass T. Napier

Kentucky Transportation Center Research Report

Standard pavement types and experimental surfaces on roads throughout Kentucky were evaluated in terms of skid resistance and effects of traffic, wear, and polishing. Friction-vs-speed gradients and the relationships between locked-wheel and incipient friction were determined. Asphaltic concrete pavements on high-speed, four-lane roads were found to be significantly more skid resistant than on two-lane highways and somewhat more skid resistant than concrete surfaces (especially those containing calcareous gravel aggregates). Sand-asphalt surfaces containing significant proportions of limestone sands showed inadequate level of friction for the traffic sustained. Several experimental sand asphalts without limestone sands exhibited greater skid resistance; Kentucky rock asphalt …

Skid-Test Trailer: Description, Evaluation And Adaptation, Rolands L. Rizenbergs, James L. Burchett, Cass T. Napier

Kentucky Transportation Center Research Report

A two-wheeled skid-test trailer and towing vehicle were acquired in 1969. The trailer was designed primarily for measurement of steady-state friction at and above normal traffic speeds. Measurement of instantaneous wheel loads also permitted determination of peak or incipient friction. Factors and variables associated with the testing device and calibration and test procedures were investigated and standardized, and the trailer was adopted for routine testing. Comparative tests with the trailers of General Motors, Ohio, and West Virginia were conducted, and the data were correlated. The interim standard method of test using an automobile was correlated with the trailer to permit …

Operational Characteristics Of Lane Drops, Don L. Cornette

Kentucky Transportation Center Research Report

Traffic behavior studies were conducted at seven lane-drop locations, representing four lane-drop classes. These studies were composed of conflict observations (consisting of both erratic movement and brakelight applications), spot-speed observations, and lane volume counts. Such a study was made before and after each different traffic control device installation in an attempt to determine which device was the most effective in minimizing conflicts at existing lane drops. A study of conflict deviations indicates that no single type of traffic control device studied was significantly effective in reducing erratic movement and brakelight rates at all seven lane-drop locations. Rather, it appears that …