Gary W. Sharpe

Road base construction utilizing coal waste materials

The paper describes the development and implementation of a no cement concrete mixture containing pulverized fuel ash (pva) and atmospheric fluidized bed combustion (afbc) byproducts as the cementitious components for combination with conventional limestone aggregates used as bulk filler. The paper presents a summary of laboratory evaluations and the application of those results to the design of a base for roadway construction. The paper also describes the construction, evaluation, and performance of a pilot application of this material used as a base for a thin bituminous pavement (a).

BREAKING AND SEATING OF RIGID PAVEMENTS

Breaking and seating have been used extensively in Kentucky to rehabilitate portland cement concrete pavements. Experience over 3 or 4 years with this type of design and construction is summarized and reported. Breaking to a range of nominal fragments is evaluated, and a report on the evaluation of two roller weights for seating is given. Also described is the use of dynamic deflections to gauge the effectiveness of the breaking and seating process and to measure the appropriateness of the asphaltic concrete overlay.

Structural Capacity of In-Place Asphaltic Concrete Pavements from Dynamic Deflections

The proper design of asphaltic overlay thicknesses involves four major factors: the in-place modulus of the subgrade, an estimate of the structural capacity of the existing pavement, estimates of the future traffic expressed AS Equivalent axleloads and required or desired design levels, and a thickness design procedure. This paper deals with estimating the in-place subgrade modulus and the remaining load-carrying capacity of the existing pavement. The method presented herein is valid for any road rater or other dynamic tester such as the dynaflect. This procedure was based upon a 600-pound (272.4-kg) peak-to-peak dynamic load applied at a rate of 25 hz. The steady-state deflections have to be adjusted for load, dynamic frequency, and location of sensors. This method should be applied only to those testers that use a constant vibratory load.(a) for the covering abstract of the conference see IRRD 815640.

Non destructive evaluation of rigid pavements using road rater deflections

The aim of this paper is to summarize and document research and developments relating to the use and application of dynamic deflection measurements (specifically Road Rater deflections) for evaluation of rigid pavements in Kentucky. Procedures have been developed to theoretically simulate measured Road Rater deflections and associated stresses and strains using elastic theory as expressed in the Chevron N-layer computer program.

PAVEMENT EVALUATION BY USING DYNAMIC DEFLECTIONS

Dynamic test deflections were duplicated by elastic theory by using the Chevron N-layered computer program. Dynamic surface deflections obtained by using the road rater were used in conjunction with elastic theory to analyze pavement behavior. A procedure was developed to use field-measured road rater deflections for the estimation of the elastic modulus of the foundation material and the determination of the equivalent thicknesses of new material that approximate the behavior of the structure. The estimated moduli and the equivalent thicknesses can be used as inputs to design overlay thicknesses. An analysis of the deflections of the first three sensors of the road rater also makes it possible to distinguish weaknesses in asphalt concrete layers from weaknesses in the supporting foundation. /Author/

Demonstration Project No. 59: The Use of Fly Ash in Highway Construction, Fayette County, Kentucky

This report summarizes preliminary site investigations, design criteria and procedures, construction criteria and procedures, and results of initial and final evaluations of an experimental road base utilizing lime kiln dust, fly ash and aggregate. Observed performance has been satisfactory. Compressive strength evaluations indicate exceptional early strength and continued strength gain of the pozzolanic base. Backcalculation of specific elastic layer moduli indicate that the modulus of the pozzolanic base material is most likely within a range of 500,000 to 1,000,000 psi. Based upon observations to date, treated bases enhance overall pavement performance and their use should be continued. It is quite probable that pavement life may be extended at reduced costs.

PAVEMENT THICKNESS DESIGNS USING LOW-STRENGTH (POZZOLANIC) BASE AND SUBBASE MATERIALS

Information is presented on combining laboratory test data for pozzolanic base and subbase materials with elastic layer theory and a limiting strain criterion to determine thickness designs equivalent to conventional asphaltic concrete and crushed stone pavement structures. A summary of laboratory testing in Kentucky is also presented. An example thickness design determination is given that includes an economic comparison of alternative designs with the conventional asphaltic concrete and crushed stone thickness design.

Structural Evaluation of Asphaltic Pavements

STRUCTURAL EVALUATION OF ASPHALTIC PAVEMENTS by Robert C. Deen, Herbert F. Southgate, and Gary W. Sharpe Transportation Research Program University of Kentucky Lexington, Kentucky

WATER UNDER PAVEMENTS

This report summarizes the construction and performance of a Cedergren-type underdrain system. Other installations of edge drains are reported for record. Outflows have been sufficient to cause minor erosion of fill slopes. Road Rater tests disclosed no weaknesses. Remaining life was estimated. (FHWA)

Low-Strength (Pozzolanic) Materials for Highway Construction

Presented at the 1983 Fall Convention, American Concrete Institute, Kansas City; Missouri , September 25-30. Publication rights reserved by the Americal Concrete Institute. Permission is granted to other journals to publish reviews, condensations, or abstracts prior to the publication of the complete paper by ACI provided these condensations do not exceed 500 words or 1/3 of the total content of the original paper, whichever is shorter, and provided acknowledgement is given to author(s) and presentation at the ACI 1983 Fall Convention.