Engineering Commons^™

Factors Affecting Asphalt Pavement Density And The Effect On Long Term Pavement Performance, Jonathan Fisher, Clark Graves, Phillip Blankenship, Salman Hakimzadeh-Khoee, R. Michael Anderson

Kentucky Transportation Center Research Report

The Kentucky Transportation Center, the Asphalt Institute, and the Kentucky Transportation Cabinet worked together in order to identify factors that affect asphalt pavement density, and to then evaluate their effect on long term pavement performance.

By determining which variables are most influential to pavement performance (i.e. roller pattern, temperature when rolled, etc.), and then monitoring the attention given to those variables, Kentucky would be able to increase the service life of asphalt roadways by at least 25%, therefore saving as much as $30 million annually on a resurfacing budget of $129.2 million (2007), while still maintaining the current roadway level …

Qc/Qa: Evaluation Of Effectiveness In Kentucky, Kamyar C. Mahboub, Paul M. Goodrum, Andy Glasglow, Jason Enlow, Nick Hendrix, Moin Uddin

Kentucky Transportation Center Research Report

Quality control and quality assurance in the highway industry is going through a cultural shift. There is a growing trend toward using the contractor data for acceptance and payment purposes. This has led to serious concerns about conflicts of interests. The question remains: are there adequate safeguards in place? To address these concerns, a number of asphalt and concrete QC/QA projects in Kentucky were examined and statistical analyses were conducted. This report presents a summary of findings and recommendations. Generally speaking, the Kentucky experience revealed that the QC/QA system is working well, and the agency’s random inspection data when compared …

Pavement Design Evaluations I-275 Boone And Kenton Counties Mp 1.05-7.15, R. Clark Graves, David L. Allen

Kentucky Transportation Center Research Report

Interstate 275 in Boone and Kenton Counties (MP 1.05 - 7.15) has been in service for more than 20 years. The eastbound lanes from MP 1.05 - 4.07 was rehabilitated by rubblization of the existing continuously reinforced concrete pavement, the addition of an open-graded drainage layer and a 9-inch PCC overlay in 1991.

Rubberized Asphalt Membrane, Kamyar C. Mahboub

Kentucky Transportation Center Research Report

This document reports findings of a study involving the use of scrap tire chips in an asphaltic membrane. The research project was designed with two objectives in mind. First, to investigate the effectiveness of an asphaltic membrane on top of a subgrade for maintaining moisture equilibrium in subgrade, and second, to study the potential use of scrap tire chips in asphaltic membranes. The effectiveness of the membrane as a moisture barrier needs to be evaluated over a long period of time (i.e. several years). However, the method proved to be a feasible alternative for recycling waste tires in pavements. It …

Bearing Capacity Analysis Of Pavements, Tommy C. Hopkins

Kentucky Transportation Center Research Report

A multilayered, mathematical model for analyzing the ultimate bearing capacity of soil subgrades and asphalt pavements is presented. Theoretical considerations and mathematical derivations of limit equilibrium equations, based on plasticity principles, for analyzing the ultimate bearing capacity of soil subgrades and partially completed asphalt pavements, and the extension of these equations to the analyses of asphalt pavements composed of multiple layers, are presented. The model is unique since shear strength parameters, Φ and c, (the angle of internal friction and cohesion, respectively) are used to describe each layer of material of the pavement structure and a factor of safety against …

Asphalt Surface Treatments For Local Roads And Streets, Ellis G. Williams

Kentucky Transportation Center Research Report

Surface Treatments are thin applications of asphalt, with or without aggregate, to an existing pavement surface. There are many types to choose from when selecting a treatment for a specific purpose.

Because of the broad range of materials and methods available, surface treatments satisfy many needs in effective operation of road and street systems. They are major tools for preventive maintenance and also satisfy many corrective maintenance needs. They are widely and effectively used as the initial surfacing over granular bases. They are increasingly used over cracked, existing surfaces to reduce reflection cracking in asphalt overlays.

It is apparent that …

Modifications To Chevron N-Layer Computer Program, Herbert F. Southgate, Robert C. Deen, David Cain, Jesse G. Mayes

Kentucky Transportation Center Research Report

This report documents changes made to the Chevron N-layer computer program to:

1. Include superposition principles.
2. Calculate strain energy density (or work) at specified locations within the pavement structure.
3. Analyze pavement response at specified radii from one circularly loaded area to permit comparison of analyses by the program as originally written with results incorporating superposition principles.
4. Evaluate pavement response to any combination of loads on circular areas defined by XY coordinates on the surface. Loads and contact pressures are permitted to be different from one loaded area to another, but must be constant for any one loaded area.
5. Simulate dynamic loads …

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.

Water-Induced Surface Failures On I 65, Hardin County, Kentucky, Ellis G. Williams, Herbert F. Southgate, Robert C. Deen

Kentucky Transportation Center Research Report

This report documents an investigation of water-related distress on portions of I 65 in Hardin County, Kentucky, on Muldraugh Hill. An open-graded surface placed on a full-depth asphaltic concrete pavement had shown areas of flushing and shallow shear failures in the outer lanes after one year of service. Cores were obtained from the outer lanes in areas exhibiting no problems to shear and flow failures. Core sites also were chosen across the lane to represent edge, wheel track, and between wheel track conditions. Visual inspection of the cores was made under normal lighting and an ultraviolet light and photographs were …

Discussion Of M.W. Witczak's A Comparison Of Layered Theory Design Approaches To Observed Asphalt Airfield Pavement Performance, Herbert F. Southgate, Robert C. Deen, James H. Havens

Kentucky Transportation Center Research Report

No abstract provided.