A Combination Waterbound Macadam and Dense-Graded Aggregate Base for Flexible Pavements

This paper is concerned with a flexible base designed primarily to improve the riding qualities of high-type bituminous pavements. Difficulties in control of grades and sections with modern methods of macadam base construction have emphasized needs for effective finishing procedures. In the project described, an 8-in. base was built in two courses, the lower waterbound macadam being overlain by a densegraded aggregate material suitable for spreading and shaping with a power grader. The base was then surfaced with two courses of a hot bituminous plant mix. Observations and measurements showed that the combination could be built satisfactorily; construction entailed more equipment but less manpower for the blade-spread course than for the waterbound macadam; the dense-graded aggregate produced a high base density; and the possibilities for finishing to uniform section were much better with the dense-graded aggregate than with the macadam

Concrete Pavement without Transverse Joints

This is a report of observations and operations pertaining to a concrete pavement without the usual transverse joints constructed during the summer of 1949. The project which is on U. S, 31-W is designated as Simpson County, FI-239 (4), and runs from Station 9+11 at the Tennessee State Line to Station 311+40 at the city limits of Franklin (See Fig. 1 for layout). It consists of a 22-foot concrete pavement underlain by 1-1/2-inches of compacted crushed limestone (Size No. 10) for insulation and leveling. The slabs are of air-entrained concrete made with the agent interground in the cement, There is a longitudinal joint at the center which is of metal with 1/2-inch deformed tie bars, but there are no transverse joints except for butt type joints at the end of each run. The paving was completed about the first of July 1949. After this pavement was built it was suggested by the Bureau of Public Roads and the Division of Construction that the Research Laboratory make observation on the general performance of this pavement. Following the first detailed observations and general inspection of the road it was decided that the pattern of crack development and particularly the character of some of the cracks warranted attention from the standpoint of crack sealing methods, Accordingly some experimental installations of crack sealing compound included in conjunction with normal routine maintenance on the road was suggested

Experimental Paving Projects using Curtiss-Wright’s Coal-Modified, Coal-Tar Binder [1962]

This report covers the observation and evaluation of 13 sections of experimental pavement constructed in Kentucky using coal-modified coal-tar binder. These are compared with the performance of control sections in which normal specification asphalt cements were used. The results of laboratory and field tests are also reported to support and supplement the visual surveys

Investigation of Concrete Pavement, US 60 between Versailles and Frankfort

A preliminary examination was made of the subject pavement on November 2, 1959, by James H. Havens and the writer, of the Research Division, and J. S. Riley, Construction Division. The discover of deleterious matter in the pavement was the major reason for the inspection. Foreign objects could be found imbedded in the concrete pavement throughout the project. However, there were a great many more in two sections, each about one quarter of a mile long, than on the rest of the project. The objects observed were wood, cloth, metal and soil. However, there was decided prevalence of soil. The soil particles seem varied in shape and ranged in size from approximately one half inch in diameter to several inches in diameter

Report No. 3 on a Concrete Pavement Without Transverse Joints

This is the third report of observations and operations pertaining to a concrete pavement without the usual transverse joints constructed in the summer of 1949. Report No. 2 which was presented to the Research Committee December, 1949, contained a detailed description of the project, pictures of the class of cracking described, a record of the crack filling operation to December, 1949, and three crack survey reports with a strip map of the project. The purpose of this report is to present three additional crack surveys taken in 1950 with the additional crack filling operations up to this time. All of the ungrooved cracks were cut out and filled with various types of fillers late in the past year, so that this type of treatment has been extended throughout the project

A Bank Gravel Base Containing Calcium Chloride [Report No. 1]

This report is concerned with a bank gravel base construction project, and particularly with that part of the base containing calcium chloride as a stabilizing agent. The project was carried out on a relocation of U.S. 62, between Kuttawa in Lyon County and Kentucky Dam on the Tennessee River. A part of the project, as shown on the general location map in Fig. 1, was in Livingston County between the Cumberland and Tennessee Rivers

Structural Repair of Concrete Pavement, Barren County Project U 543(3)

The Research Division assisted the District Construction personnel with structural repairs of five areas of cement concrete pavement that had been adjudged unsatisfactory. I had an opportunity to observe the repaired areas on July 19, 1962, and they all appear to be performing. adequately. The color of the epoxy patching material does not completely match the adjacent concrete but with normal weathering the two materials should approach a better match

Evaluation of Plant Mix Surface Treatments

This project made use of six bituminous materials and ten aggregate gradations in plant mix paving operations. The test sections were installed by state forces in 1942 and 1943. The object was to determine which aggregate gradation with a specific bituminous material was best suited for an application of 75 pounds per square yard surface treatment. The bituminous materials used were MC-5, RC-5, RT-12, PAC-5 (85 to 100 penetration), PAC-7 (120 to 150 penetration), and PAC-8 (150 to 200 penetration). Twenty sections of MC-5 and ten sections of RC-5 were laid in 1942; all the sections containing the other materials were placed in 1943. A lay-out of the project by sections is shown in Fig. 1. There were three aggregates or aggregate combinations as follows: Limestone, Limestone and Concrete Sand, and Limestone and River Sand. The Limestone type consisted of four gradations made from mixing No. 9 and a fine stone designated as No. 11F. The Limestone and Concrete Sand type consisted of three gradations of No. 9 stone and the coarse sand. The Limestone and River Sand type consisted of three combinations of River Sand and No. 9 stone. These ten gradations are outlined in Table 1 and shown on the gradation chart in Fig. 2. The gradation range for the 11F stone used in gradings G-1 to G-4 is in Table 1A. This was a much finer stone than the present No. 11 outlined in the same table. A plot of these gradation ranges along with one representing the Kentucky River sand is presented in Fig. 3

A Limestone-Calcium Chloride Stabilized Base

This report is mainly concerned with the calcium-chloride stabilized portion of a combination base. A 4-inch course of waterbound macadam was placed over a 1-inch insulation course overlying an existing traffic-bound stone surface. The next 4 inches of base above, the water bound material consisted of two 2-inch layers of calcium-chloride stabilized limestone of a design not used heretofore by the Department. Bituminous concrete binder and surface courses laid over the base brought the total mat thickness to more than 11 inches. The surface width was 30 feet, and the length of the project was 1.1 miles. Although the road is located about 2 miles south of the Lexington city limit, it serves an area which is essentially urban. In addition it is a link between U.S. 27 and U.S. 68 as shown in the sketch map of Fig. 1. The traffic volume anticipated in the near future is approximately 1500 vehicles per day of which a fairly large percentage will be commercial because of the business and industrial zone nearby and the convenience this route offers in avoiding congested streets within Lexington carrying U.S. 27 north and south. From an investigational standpoint, interest was centered on the so-called stabilized courses, not only because of the unusual stone gradation involved but also the feasibility of mixing and spreading these courses with patrol graders. This process was under observation as a means for simplifying macadam construction and improving the riding qualities of the finished pavement. The length of the project limited possibilities for comparison that would apply to simplified construction procedures; however, the length was not considered an important influence on placement of the base in its relation to improved riding qualities