Engineering Commons^™

Letter From Dr. Otis A. Singletary, Otis A. Singletary

Kentucky's Annual Forum on Transportation

No abstract provided.

Letter From C. Leslie Dawson, C. Leslie Dawson

Kentucky's Annual Forum on Transportation

No abstract provided.

Summary Of Experimental Bridge Features, Theodore Hopwood Ii, James H. Havens, Edgar E. Courtney

Kentucky Transportation Center Research Report

Experimental bridge features and service problems investigated during this study are reviewed. Those were epoxy-coated reinforcing steel, stay-in-place forms, experimental deck features (rotary compaction and broomed deck finishing), precast segmental bridges, steel-corrosion control methods (weathering steel and hot-dipped galvanizing), microsilica concrete, failures of masonry coatings, and failures of aluminum guardrail-retaining nuts.

Several features including latex and low-slump overlays, epoxycoated reinforcing steel, and broomed deck finishes (for state-built bridges), are now in common use. Most of the other experimental bridge features were performing satisfactorily. A corrosion problem was observed on one weathering steel bridge. Analyses of failures of masonry coatings and …

Acoustic Emission Monitoring Of Bascule Bridge Components, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

During September 4-16, 1986, Kentucky Transportation Research Program (KTRP) personnel conducted a two-week inspection of welding operations on bascule bridge components for the Wisconsin Department of Transportation (WisDOT). Welding was performed by the Phoenix Steel Company at Eau Clair, Wisconsin. The inspection was conducted using acoustic emission (AE) monitoring on in-process welds.

KTRP investigative experience with AE weld monitoring and testing of bridges began in 1973. Since that date, KTRP has performed nine series of laboratory and fabrication shop weld monitoring tests and conducted 20 field tests of bridges using a series of increasingly sophisticated AE devices. Over the past …

Design And Performance Of Highway Shoulders, David Q. Hunsucker, Gary W. Sharpe, Robert C. Deen

Kentucky Transportation Center Research Report

This report summarizes finding of a long-term evaluation of the construction and performance of asphaltic concrete and portland cement concrete shoulders. Performance was used as the basis for the development of empirical criteria that permit the use of existing pavement thickness design procedures for the structural design of shoulders. Minimum thicknesses were determined on the basis of performance and review of literature.

Traffic Control And Accidents At Rural, High-Speed Intersections, Kenneth R. Agent

Kentucky Transportation Center Research Report

The site characteristics, traffic control used, and accidents occurring at 65 rural, high-speed intersections were summarized. The differences resulting when the right of way is controlled by stop signs versus a traffic signal are discussed. The factors contributing to the accidents as well as the characteristics of the accidents were analyzed. The data obtained at each intersection were summarized and recommendations, which could be used as a guide for implementing changes at other similar intersections, were made for the study locations. The accident analysis shows that providing the driver adequate warning of the intersection is of primary importance for this …

Civil Engineering Applications Of Acoustic Emission, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

In 1939, a suspension bridge at Portsmouth, Ohio, experienced stress-corrosion cracking of the main-cable wires at anchorage points located at each end of the bridge. Watchmen were placed in the anchor chambers where the fractures had been detected. Subsequently, they reported hearing the sounds of further wire breakage on quiet nights. When this was reported, a decision was made to recable the bridge (1). That was one of the earliest documented instances of the use of the acoustic emission phenomena in a structural application.

Also, in the late 1930's, L. Obert and W. I. Duval at the U. S. Bureau …

Bridge Decks And Overlays, James H. Havens, Theodore Hopwood Ii, Edgar E. Courtney

Kentucky Transportation Center Research Report

The report presents a historical perspective of the Transportation Cabinet's bridge deck construction and maintenance efforts directed toward increasing bridge deck durability.

Bridge decks crack in specific patterns that primarily depend upon bridge designs. Normal deck cracking is due to load-induced and thermal effects. Each type of cracking has a distinct pattern.

One-hundred and nineteen experimental bridge deck overlays were inspected. Included were 9 membrane bridges, 87 latex concrete overlays and 23 low-slump overlays. The overlays had been placed originally on both new and existing bridge decks on various routes throughout the state. Most of the overlays were rated in …

Automated Data Acquisition For Low-Volume Road Inventory And Management, Theodore Hopwood Ii, Gary W. Sharpe, John W. Hutchinson, Robert C. Deen

Kentucky Transportation Center Research Report

Local governments need suitable inventories and condition surveys to accurately determine and prioritize their funding needs. An efficient method of performing an inventory of the roads and subsequently determining the condition of major system components is to use an automated data-acquisition system to measure and record essential data. The data may be collected and processed by a central inventory management group. The inventory should include pavement characteristics, roadway geometries, and roadside features. Pavement condition may include structural integrity, road roughness, and skid resistance. Roadway geometries include horizontal curvature, length, width, superelevation, and grade. Roadside features include signing, intersections, guardrails, and …

Evaluation Of 1985 Aashto Flexible Pavement Design Equations And Nomographs, Herbert F. Southgate, Gary W. Sharpe, Robert C. Deen

Kentucky Transportation Center Research Report

The 1985 AASHTO nomograph and equations for flexible pavements were reviewed and analyzed to determine requirements for input data, sensitivity of designs based on the additional variables for percent reliability, standard deviation, and resilient modulus of subgrade material. Design thicknesses using the 1985 AASHTO Guide were compared to thicknesses using the 1981 Kentucky thickness design method for flexible pavements.

Status Report For Selected Projects Containing Experimental Features, Kentucky Transportation Research Program

Kentucky Transportation Center Research Report

Projects containing experimental features or innovative concepts were selected for long-term monitoring and are reported herein. Certain projects are recommended for more intensive investigation under other appropriate ongoing studies.

Impact Evaluation Of The Lexington-Fayette County Traffic Alcohol Program (1982-1986), Jerry G. Pigman, Kenneth R. Agent

Kentucky Transportation Center Research Report

This report is a final evaluation of four years of increased police enforcement to reduce alcohol-related accidents in Lexington-Fayette County, Kentucky. Three types of data were collected 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 four years during the increased enforcement, the reduction in alcohol-related accidents during hours of increased enforcement was 37.3 percent using standard before and after analysis and 36.4 percent using time-series analysis. For all …

Investigation Of Collapse Of Long-Span Structure Under Ky 80 In Floyd County, Ronald D. Hughes, David L. Allen, Robert C. Deen

Kentucky Transportation Center Research Report

The Kentucky Transportation Research Program (KTRP) was requested to obtain and review design, construction, and post construction documents relative to the long-span structure under KY 80 in Floyd County. Telephone and in-person contacts were made with various agency officials involved with the structure in an endeavor to collect pertinent data. Documents that were initially presented to KTRP staff were thoroughly reviewed and a draft report based upon information submitted was prepared. The draft report included a scenario relating to a probable sequence of events that could have been significant in the ultimate collapse of the structure.

Soon after distribution of …

Shrinkage Compensation Deck Concrete (Ky 1974 Bridge Over Tates Creek Road), David Q. Hunsucker

Kentucky Transportation Center Research Report

This report summarizes the construction activities on an experimental bridge deck utilizing shrinkage compensating concrete. The experimental concrete is characterized in terms of freeze/thaw durability, compressive strength, and elastic moduli.

Rutting And Longitudinal Cracking And Temperature Cracking: A Case Study (Us 23, Greenup County, Mp 6.0 To 28.8), James H. Havens, Gary W. Sharpe, David L. Allen, David Q. Hunsucker

Kentucky Transportation Center Research Report

US 23, Greenup County, Ashland-South Shore, developed rutting and transverse and longitudinal cracking. The pavement was about 14 years old and had served heavy trucks. Road Rater tests, crack surveys, and various inspections had been made prior to the fall of 1985. Inspection and a report by KTRP led to further evaluation, examination internally by trenching, and additional tests and surveys. This report combines pertinent facts and records. It includes recommendations for overlayment.

Lime Stabilization Of Pavement Subgrade Soils Of Section Aa-19 Of The Alexandria-Ashland Highway, Tommy C. Hopkins, David L. Allen

Kentucky Transportation Center Research Report

The purposes of this study were to evaluate the effects of hydrated lime on the soils from Section AA-19 of the Alexandria-Ashland Highway and determine if the engineering properties of the soils from Section AA-19 could be improved by lime stabilization. Soil samples used in the study were obtained by· the Kentucky Transportation Research Program on March 25, 1986. Three bag samples were collected from Section AA-19 (Lewis County, Kentucky) of the Alexandria-Ashland Highway, Stations 1630 (Sample A), 1495 (Sample B), and 1675+50 (Sample C), respectively. Based on a review of the geology of Section AA-19, the three sampling sites …

Design Of Highway Embankment On Unstable Natural Slopes, Charles S. Bishop, Donald W. Armour Jr., Tommy C. Hopkins

Kentucky Transportation Center Research Report

Sections of the new Alexandria-Ashland (M) highway in northeastern Kentucky must be located on and through natural slopes of the Kope and Crab Orchard Formations that consist mainly of shales. Numerous highway embankment and cut slope failures have occurred In these two geologic formations In past years. The shales of these formations have very poor and undesirable engineering properties. Many stability problems encountered with the Kope and Crab Orchard shales are caused primarily by the tendency of those shales to breakdown when exposed to water and produce clays and clayey silts of relatively low shear strengths. Construction of highway embankments …

Distributions Of Strain Components And Work Within Flexible Pavement Structures, Herbert F. Southgate, Robert C. Deen

Kentucky Transportation Center Research Report

An investigation was made to determine the location along the centerline of the axle of the maximum strain energy density, or work, in the pavement as defined by classical physics. The location is under the inside edge of either dual tire. The most influential strain was the shear component. The distribution of shear strains and stresses with depth through the full-depth asphaltic concrete and into the subgrade was investigated. Using Simpson's rule for an even number of increments, or using the trapezoidal rule, allows the summation of strain energy density calculated at various depths. This sum multiplied by a unit …

Manual On Bridge/Culvert Maintenance, Gary W. Sharpe, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

The basic objective of this course is to provide background (introductory) technical information that will aid the manager of bridge/culvert installations. In most instances, information presented may not be sufficiently complete for the student to perform the required work. However, the intent is more to familiarize than to instruct In many instances, professional engineering and experienced labor are necessary to ensure successful completion of tasks. Once the local official responsible for bridges and culverts has completed this workshop, he should have a basic understanding of

• the most common bridges/culverts encountered in counties and municipalities,
• the major components of common bridge/culvert …

1986 Safety Belt And Child Safety Seat Usage Rates In Kentucky, Kenneth R. Agent

Kentucky Transportation Center Research Report

The objective of the survey summarized in this report is to establish 1986 safety belt and child safety seat usage rates in Kentucky to compare to those determined from previous surveys. Also included in this report is an analysis of accident records evaluating the effectiveness of safety belts.

Statewide usage rages in the 19 cities previously surveyed in 1982, 1983, 1984, and 1985 showed that driver safety belt usage increased in 1986 while child safety seat and safety belt usage remained at the 1984 and 1985 levels. The statewide usage rate of safety belts by drivers was 13.0 percent in …

Evaluation Of I-75 Lane Closures, Jerry G. Pigman, Kenneth R. Agent

Kentucky Transportation Center Research Report

A project on I 75 in Whitley and Laurel Counties during the 1986 construction season involved numerous lane closures associated with spot pavement replacement and joint sealing. Traffic congestion associated with heavy volumes and late merges resulted in the use of the following traffic control devices to supplement standard lane closure devices; 1) variable message signs, 2) supplemental lane closure warning signs, and 3) rumble strips placed in the lane to be closed in advance of the taper.

Results showed a decrease in the percentage of traffic in the lane to be closed with each successive traffic control device in …

Traffic Forecasting For Pavement Design, Harshad R. Desai, Rick Reel, Robert C. Deen, Herbert F. Southgate, Ronald Noble, Vernon L. Tabery, Mark Hallenbeck, Dennis Crimmins, Wiley Cunagin

Kentucky Transportation Center Research Report

The need for improved traffic estimation procedures has been emphasized by several studies that demonstrated that previously available data were not adequate. Some data were not considered representative of actual traffic conditions because of overloaded trucks avoiding weighing scales and insufficient traffic sampling programs. In addition, previous forecasting procedures did not reflect the increases in legal load limits, the significant increase in the number of heavy trucks, or the shift toward larger vehicle types that has occurred in recent years.

Improved estimates of current traffic loadings based on larger samples of much higher quality data would allow development of procedures …

Performance Monitoring Of A Highway Tieback Wall (I 71, Carroll County, Ky 227, Corrective Landslide Measure), Bobby W. Meade, David L. Allen, Tommy C. Hopkins

Kentucky Transportation Center Research Report

A tieback wall was used to control an earth slide on KY 227 in Carroll County. Herein is contained a description of the wall construction and problems encountered during construction. Also included are descriptions of materials used and wall components.

The short-term wall performance indicates the tieback wall has controlled the earth slide and, to date, is a satisfactory solution. Long-term monitoring of the tieback wall will continue.

Economic Analyses Of Millings, Herbert F. Southgate

Kentucky Transportation Center Research Report

Economic analyses were made using 1984 and 1985 contract bid data. Data were identified as to who retained ownership. Recommendations as to who retains ownership are made based upon factors prevalent for a specific candidate pavement and other circumstances.

Evaluation Of Snowplowable Marker Installations, Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

The first large-scale contracts for the installation of snowplowable markers were awarded in 1984 and 1985. Stimsonite 96 and recessed markers were installed. The objective of this study was to evaluate the performance of the installations. Durability and reflectivity results show that both the recessed markers and Stimsonite 96 markers have performed effectively as snowplowable markers. The recessed markers should continue to be used only on four-lane highways constructed to high geometric standards with the Stimsonite 96 markers installed on the majority of highways.

Thickness Design Curves For Asphaltic Concrete On A 4-Inch Layer Of Dense-Graded Aggregate, Or On 6, 9, Or 12 Inches Of Stabilized Soil, Or For Maximum Utilization Of Dense-Graded Aggregate, Herbert F. Southgate

Kentucky Transportation Center Research Report

No abstract provided.

Evaluation Of Durable Lane Delineation Materials, Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

The objective of the study was to evaluate the cost-effectiveness of available marking materials by means of field tests and to make recommendations concerning the optimum lane delineation materials based on these tests. Materials tested include 100-percent solid epoxy paint, polyester paint, extruded thermoplastic, 3M Stamark tape, 3M Bisymmetric tape, EPOFLEX, solvent epoxy paint, chlorinated rubber traffic paint, and alkyd traffic paint. The test installations have been in place up to four years. The evaluation concerned the durability, reflectivity, and appearance of the materials. Based on current data, expanded use is warranted for 1) polyester paint on lower-volume asphaltic concrete …

Evaluation Of Durable Crosswalk And Stopbar Marking Materials, Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

The objective of this study was to find the most cost-effective durable marking material to provide long-lasting stop bars and crossbars. Three materials were tested: 1) 3M Stamark tape, 2) Prismo preformed tape, and 3) extruded thermoplastic (hydrocarbon and alkyd). The various test installations were in place for between 6 and 30 months.

The alkyd-resin thermoplastic material was found to be the most cost-effective I material. The preformed tapes cost two to three times as much as the thermoplastic material while not providing as durable a material when used in this application.The alkyd-resin material maintained its appearance better than the …

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 …