Transportation Engineering Commons^™

Effects Of The Energy Crisis On Traffic In Kentucky, Kenneth R. Agent, Donald R. Herd, Rolands L. Rizenbergs

Kentucky Transportation Center Research Report

The Arab oil embargo in mid-October 1973 curtailed availability of gasoline. Fuel conservation measures resulted in reduced travel and decreased traffic speeds. On March 1, 1974, posted speed was set at 55 mph on rural highways in Kentucky. Traffic volumes, speeds, and accidents for the rural highway during the period known as the "energy crisis" and its after effects were compared to the corresponding period a year earlier.

Traffic volumes began to decline in December 1973 but began to rise again in March 1974. Total travel in the seven months through June 1974 decreased by 3.5 percent; traffic increased by …

Experimental Portland Cement Concrete Shoulders Design And Construction, James H. Havens, Assaf S. Rahal

Kentucky Transportation Center Research Report

Kentucky's first portland cement concrete shoulder project was conceived in 1970 and was inspired by the Portland Cement Association's issue Concrete Shoulders for Safe Modern Highways, Concrete Report, 1970, and FHWA's Informational Memorandum CMPB-17-70, Experimental Project for the Evaluation of Portland Cement Concrete Shoulders Adjacent to Concrete Mainline Pavement; Project Prospectus, National Experimental and Evaluation Program; May 12, 1970. It was expected that at least two states in each region would participate in the national program. A 3.442-mile section of US 31 W, between Radcliff and Tiptop, beginning at the intersection of US 60 and extending southward, …

Skid Resistance Studies In Kentucky (An Overview – 1974), James H. Havens, James L. Burchett, Rolands L. Rizenbergs

Kentucky Transportation Center Research Report

"To free Kentucky of slick roads" is the high goal toward which Kentucky has been striving since 1950's. A very capable fellow engineer used to say that there was more satisfaction in being able to take down a Slippery When Wet sign than in erecting one.

Considerable effort has been devoted to the development and adaptation of improved methods of skid resistance testing and to the standardization of testing devices (1, 2, 3, 4). Methods of tests have included the NCSA friction wheel (bicycle wheel), automobile deceleration, skewed-wheel (skewed front-wheels of an automobile), skidding automobile, and the skid-test …

Heating The 9th Street Interchange, Louisville, Ky, James H. Havens

Kentucky Transportation Center Research Report

The 9th Street interchange, I 64-2(87)3, was first conceived about 1959. Preliminary design studies began in the early 1960's. Design began about 1964. The idea of heating the ramps was first considered in the early 1960's but was not pursued intently until the final design stage (about 1968). As the design progressed, it became more and more evident that snowing and icing conditions could prevent otherwise normal passage of traffic up and down the ramps. At one point on the structure, a combination of superelevation and grade would produce a 6 1/2 percent slope. The highest ramp or "fly over" …

A Rock Classification Schema, Robert C. Deen, C. D. Tockstein, M. W. Palmer

Kentucky Transportation Center Research Report

The need for engineering data on earth materials for use in site selection, design, construction, and maintenance of major engineering structures is generally accepted. Probably the most pressing need is for such data to use in preliminary considerations of site selection and design alternatives. Maps and(or) surveys giving the areal distribution of earth materials and their characteristics, together with topographic maps available for many areas, would permit much preliminary work on engineering structures to be done without the engineer ever having to leave his office.

High-Intensity Reflective Materials For Signs, Rolands L. Rizenbergs

Kentucky Transportation Center Research Report

Field observations and laboratory tests and evaluations were conducted on High-Intensity and Engineering Grade materials (Scotchlite), manufactured by the Minnesota Mining and Manufacturing Company, and were compared in regard to reflectivity, durability, and cost.

The High-Intensity Grade materials were found to have outstanding performance characteristics in comparison to Engineering Grade materials. The material significantly enhances sign legibility under low-beam illumination, and accelerated weathering tests showed superior durability.

Optimal Highway Safety Improvement Investments By Dynamic Programming [Aug. 1974], Jerry G. Pigman, Kenneth R. Agent, Jesse G. Mayes, Charles V. Zegeer

Kentucky Transportation Center Research Report

The process of determining which projects to implement under a given budget, and which to defer until later, is central to the planning and management of highway systems. With a limited budget for construction, maintenance, and safety improvements, investments which will produce the optimal benefits must be chosen. This is often impossible to accomplish without the aid of a computer because of the complexity of the problem. Dynamic programming has been tested and verified as an efficient method for selecting priority projects to derive maximum benefits.

There are several approaches to priority programming as it is related to the capital …

"Before" Evaluation Of Economic Growth Center Developmental Highway (Ky 55, Campbellsville-Lebanon), Joseph T. Farmer, Jerry G. Pigman

Kentucky Transportation Center Research Report

Before-and-after impact studies were selected as the means of determining the effect of reconstructing a 4.813-mile (7.744-kilometer) section of KY 55 between Campbellsville and Lebanon. The area, though still depressed in terms of per capita income and employment, has many resources available for growth. The study area is predominantly an agriculturally-oriented economy. However, manufacturing employment has increased in recent years, mainly because of industrial sites made available by local industrial commissions.

Overall, social services appear to be adequate and very near statewide averages. Recreational facilities are not highly developed and are primarily of the summer outdoor type.

Reconstruction of KY …

Temperature Distributions In Asphaltic Concrete Pavements, Herbert F. Southgate

Kentucky Transportation Center Research Report

The straight-line relationship between temperatures at a given depth and the surface temperatures combined with 5-day average air temperatures appears to be as valid for upper New York State and Arizona as it was for Maryland. The main differences were in the ranges and mean temperatures. Values given herein are for straight-line equations for all 24 hours and for the depths of 2, 4, 6, 8, 10, and 12 inches (5.1, 10.2, 15.2, 20.3, 25.4, and 30.5 cm). The original concept appears to be valid and may be used with confidence for estimating pavement temperatures at other latitudes and longitudes.

Acoustic Emission Testing Of Shielded Metal-Arc Welds Using Astm A 36 Steel, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

Manual, shielded metal-arc welds on ASTM A 36 structural steel were monitored with acoustic emission equipment. The listening device detected operator inconsistencies and improper electrode deposition during the welding operation. On completion of the weld, acoustic emission monitoring detected slag inclusions, cracking, and martensite formation.

Identification Of Hazardous Locations On Rural Highways In Kentucky, Charles V. Zegeer

Kentucky Transportation Center Research Report

The purpose of this study was to determine the most effective method of identifying hazardous locations for on-site investigations. To decrease the possible effect of random or spurious accidents on the identification of hazardous locations, a 0.3-mile (0.48-km) segment was chosen along with 1- and 2-year periods for accumulating and comparing accident data. An optimal method for identifying hazardous locations and sections was determined to be one which (1) maximizes benefits from improvements, (2) identifies locations with critically high accident rates, and (3) identifies potential hazards. A sample of 170 locations was used to compare several location-identification methods. The procedure …

Shear Strength Of Cohesive Soils And Friction Sleeve Resistance, Vincent P. Drnevich, C. Thomas Gorman, Tommy C. Hopkins

Kentucky Transportation Center Research Report

Cone penetrations tests were performed on the silty clays of Kentucky, U.S.A., using a boring rig to push the Dutch, friction sleeve, cone penetrometer. Thin-walled tube samples were taken from nearby boreholes. For the first four sites, unconfined compression tests and unconsolidated-undrained triaxial test were performed on the samples. For the last four sites, consolidated-undrained triaxial tests were performed on the samples. A procedure for estimating in situ shear strength from triaxial test stress paths was developed.

Small rock fragments in these residual soils caused erratic cone resistance at many locations. As a result, the friction sleeve resistance provided the …

Operational Characteristics Of Lane Drops, Don L. Cornette, Robert C. Deen, James H. Havens

Kentucky Transportation Center Research Report

Traffic behavior studies were conducted at seven lane-drop locations, representing three lane-drop classes. These studies consisted of conflict observations (that is, erratic movements 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 different traffic …

"Before" Evaluation Of Economic Growth Center Developmental Highway (Us 25e: Corbin-Barbourville), Joseph T. Farmer, Jerry G. Pigman

Kentucky Transportation Center Research Report

Before-and-after impact studies were selected as the means of determining the effect of reconstructing a 4.886 mile (7.862 kilometer) section of US 25E between Corbin and Barbourville. A comprehensive analysis of the "before" statistics revealed the area designated as a potential growth center suffered from social and economic mediocrity. Many characteristics considered essential for economic prosperity are lacking. Per capita income and educational achievement levels are lower than statewide averages. Transportation is dependent upon highways and many existing routes provide a very low level of service.

On the other hand, the area has adequate industrial and recreational potential to insure …

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

Kentucky Transportation Center Research Report

In September 1971, the U.S. House of Representatives Subcommittee on Investigations and Oversight met in Covington, Kentucky, to discuss the accident experience and remedial procedures taken to alleviate the frequency of accidents occurring on approximately five miles of I 75 just south of Cincinnati. This section of highway had been and was continuing to be the subject of several safety improvements. The objective of this study was to conduct before-and-after investigations of the effectiveness of the following safety improvement projects: (1) five variable message signs within a two-mile section, (2) a New Jersey-type median barrier wall extending approximately four miles, …

A Rock Evaluation Schema For Transporting Planning In Kentucky, C. D. Tockstein, M. W. Palmer

Kentucky Transportation Center Research Report

The initial goal was to devise an engineering classification system for intact rock samples based on simple index tests which could be used to categorize Kentucky surface and near-surface rock types and assist Kentucky Department of Transportation personnel in planning for transportation facilities. While conducting the literature survey, several facts become apparent:

1. a large number of rock classification systems, geologic and technical, general and specific, already existed;
2. an equally large number of index tests had been devised; and
3. there was a lack of communication among those involved in specialized areas of rock-related work (geologists, civil engineers, mining engineers, etc.), and, …

Loads On Box Culverts Under High Embankments, Harry F. Girdler

Kentucky Transportation Center Research Report

The structural design of culverts requires a reliable estimate of the earth pressures which will come to bear on the structure during and after construction of the embankment. The actual bearing pressure at a given time and under various conditions of differential settlement may be greater or less than the deadload of the fill or embankment over the structure. This report describes the instrumentation and construction of three box culverts designed by the imperfect trench method. A total of 42 Carlson earth pressure cells were installed in conjunction with strain gages and settlement measuring devices, including inverted settlement plates and …

Relationships Between Roadway Geometrics And Accidents (An Analysis Of Kentucky Records), Kenneth R. Agent

Kentucky Transportation Center Research Report

Statewide average and critical rates of accidents were determined from 1970-1972 Kentucky accident records for each type of rural highway. Four-lane undivided highways had the highest average accident rate; parkways (toll roads) had the lowest rate. The severity of accidents was related to types of accidents, highways, and traffic control and to safety belt usage. Accidents involving pedestrians were the most severe types; single-vehicle accidents ranked next highest in severity. Excluding accidents at railroad crossings, accidents which occurred on curves had the highest severity index. The use of safety belts was associated with reduced severity.

Raised Pavement Markers As A Traffic Control Measure At Lane Drops [No. 418], Jerry G. Pigman, Kenneth R. Agent

Kentucky Transportation Center Research Report

Raised pavement markers are an effective means of reducing erratic movements at lane-drop locations, particularly under nighttime driving conditions. The cost of raised pavement markers and their installation is nominal (approximately $150 per lane-drop location). It is recommended that raised pavement markers be installed at other lane-drop locations. Markers installed at locations described in this study have not been in place for a sufficient time to determine their durability; however, reports from other states indicate their durability is sufficient to render them economical. If raised pavement markers are installed routinely, steps should be taken to insure they are not damaged …

Raised Pavement Markers As A Traffic Control Measure At Lane Drops [No. 384], Jerry G. Pigman, Kenneth R. Agent

Kentucky Transportation Center Research Report

Raised pavement markers are an effective means of reducing erratic movements at lane-drop locations, particularly under nighttime driving conditions. The cost of raised pavement markers and their installation is nominal ($150 per location). It is recommended that raised pavement markers be installed at other lane-drop locations. Markers installed at locations described in this study have not been in place for a sufficient time to determine their durability; however, reports from other states indicate their durability is sufficient to render them economical. If raised pavement markers are installed routinely, steps should be taken to insure they are not damaged by snowplow …

Porous Sand-Asphalt Mixtures, James H. Havens

Kentucky Transportation Center Research Report

Size is relative. Densely graded sand-asphalts are relatively similar to conventional, bituminous concretes. Porous sand-asphalts possess the same attributes as other porous, bituminous mixtures. Surely, sand-asphalt mixtures, can be designed to be as porous as the so-called, open-graded plantmix seals. Particle shape and texture otherwise define skid-resistance. Stability remains an assurance against scaling. Stability is assured by maximum utilization of filler-bitumen ratio and the stiffness of asphalt cement.

Recommendations For Implementation Of Uniform Project Identification From The Upi Task Force, Herbert F. Southgate

Kentucky Transportation Center Research Report

For years project identifications have been based upon county, section, subsection, and phase of work. While this system worked well in the beginning, overlay constructions, widening efforts, etc. have caused overlapping of projects to the point that identification of a given portion of a highway has become very difficult. Furthermore, each of the many separate phases of work has its own project number and may not be so readily identifiable as the succeeding work phase.

Management came to realize there was a need for a numbering identification system that would be readily understandable. The direct result was the development of …

Traffic Control For Maintenance On High-Speed Highways, William M. Seymour, Robert C. Deen, James H. Havens

Kentucky Transportation Center Research Report

Observations were first made at lane closures on interstate highways where yellow warning signs were erected routinely in conjunction with contract work. Later data provided direct comparison between new yellow and new orange signs. One sign scheme was used throughout the study. Driver obedience improved when new signs of either color were used; this finding implies that signs should always be maintained in good condition. Orange signs were slightly more effective than yellow signs in reducing traffic conflicts and merges near the traffic cones. Results of the study tend to support the adoption of orange as the standard color for …

Auto-Utility Trailer Combinations On Rural Highways In Kentucky, Bruce S. Siria, Robert C. Deen

Kentucky Transportation Center Research Report

An analysis of accident records indicated that auto-utility trailer (A-UT) combinations are involved in a disproportionately high number of traffic mishaps. Locations which have a history of accidents involving A-UT vehicles indicated that differential crosswinds and unanticipated driving maneuvers contribute to the driver's loss of control. A-UT combinations contributed to the fatigue loss in pavement life approximately 50 percent as much as single-unit, two-axle, six-tire trucks (per vehicle). In general, this vehicle type constituted approximately three percent of the total traffic stream. Analysis of speed distributions indicated an equivalency factor for A-UT combinations equal to that for trucks for similar …

The Creep Response Of Cohesive Soils: A Method Of Design Using Rheological Strength Parameters, David L. Allen

Kentucky Transportation Center Research Report

The creep response of four remolded soils and undisturbed soils from two landslide sites is presented. A method for obtaining the yield stress of soil from creep test data is presented and discussed. "Viscosity diagrams", showing the location of the yield stress is approximately 50 percent of peak stress, were obtained from conventional triaxial tests. There is more scatter in data from undisturbed soils than in data from remolded soils. Mohr's failure envelopes, constructed from yield stress data, give internal friction angles having values from approximately five to ten degrees. Strength data, calculated indirectly from peak relaxation modulus, are also …

Traffic Accident Reporting In Kentucky, Donald R. Herd

Kentucky Transportation Center Research Report

This study reviews the organizational structure and processing procedures used in accident surveillance. Consideration was given to the techniques that various state governmental agencies use in their analysis of accident reports and statistics. It was concluded that Kentucky should enact uniform accident reporting legislation. A standard form should be prescribed for use by law enforcement agencies in complying with the reporting requirement. The creation of an Accident Records Unit to receive, process, and statistically analyze the reports is recommended.

Evaluation Of The Traffic Noise Prediction Procedure, Kenneth R. Agent, Charles V. Zegeer

Kentucky Transportation Center Research Report

Approximately 270 noise-level recordings were obtained at 39 highway sites and compared with the noise-level predictions obtained by the procedure outlined in NCHRP Report 117. The measured noise levels were computed in terms of the A-weighted L₁₀ value (level exceeded 10 percent of time) and then compared to the predicted noise levels. A significant discrepancy was found between predicted and measured noise levels; generally, the predicted values exceeded the measured values. Average error per location was 4.8 dBA; the maximum error was 13 dBA. A nomograph was devised to correct the predicted value; this nomograph involves observer-to-roadway distances, truck …

Accidents On Rural Interstate And Parkway Roads And Their Relation To Pavement Friction, Rolands L. Rizenbergs, James L. Burchett, Cass T. Napier

Kentucky Transportation Center Research Report

Friction measurements were made with a skid trailer at 70 mph (31 m/s) on 770 miles (1240 km) of rural, four-lane, controlled-access routes on the interstate and parkway systems in Kentucky. Each construction project was treated as a test section. Accident experience, friction measurements, and traffic volumes were obtained for each. Various relationships between wet-weather accidents and skid resistance were analyzed. The expression of accident occurrence which correlated best with skid and slip resistance was wet-weather accidents per 100 million vehicle miles. Accidents increased greatly as Skid Numbers (70 mph or 31 m/s) decreased from 27 ± 1. Analysis of …

In Situ Shear Strength Parameters By Dutch Cone Penetration Tests, C. Thomas Gorman, Tommy C. Hopkins, Vincent P. Drnevich

Kentucky Transportation Center Research Report

Dutch cone penetration testing was performed and undisturbed samples were collected at four Kentucky highway sites. Shear strength, as determined by consolidated, undrained triaxial testing of the undisturbed samples, was correlated with friction resistance as measured by the Dutch friction cone. Statistical analysis of all data showed shear strength to be about 80 percent of friction resistance. Recommendations for the use of the Dutch cone penetration test in Kentucky soils were also made.

Design Guide For Bituminous Concrete Pavement Structures, James H. Havens, Robert C. Deen, Herbert F. Southgate

Kentucky Transportation Center Research Report

The proposed design guide includes procedures for estimating design EAL's, CBR, modulus of the asphaltic concrete, and an array of tables and graphs to determine pavement and layer thicknesses.