Durability and Durability Tests for Paving Asphalt: A State-of-the-Art Report, HR-124, 1969

This special report is prepared to review durability and durability tests for paving asphalt, both in theory and in application. The report summarizes and evaluates factors related to asphalt durability, problems associated with durability study and development of durability tests, important work on durability and practical design implications concerning asphalt durability. It is a state-of-the-art report and a part of the study under HR-124, Development of Laboratory Durability Test for Asphalts.

Absorption of Asphalt by Aggregate, HR-142, Progress Report, 1970

This report summarizes work accomplished under Project HR-142 during the period from January 1, 1969 to December 31, 1969. Pore characteristics of six limestones were studied in relation to their absorption of two asphalt cements. Porosity and pore size distribution were determined by a mercury penetration porosimeter and asphalt absorption was determined by immersion and bulk-impregnated specific gravity methods. A special study was conducted to develop new, simple and more reproducible methods for bulk specific gravity determination. As a result, a new chemical indicator method was developed to determine the saturated surface-dry condition, and a glass mercury pycnometer was designed to determine coarse·and fine aggregates. Asphalt absorption history of one asphalt mixture on campus has been studied since September 1968. Chemical and/or radiation treatments of absorptive aggregates were conducted on four chemicals and two aggregates.

Improvement of Longitudinal Joints in Asphalt Pavement, HR-215, Construction Report, 1981

One significant benefit of asphalt concrete pavement construction is that it may be opened to traffic within one hour after being laid. Therefore, road closure and detour are not necessary, but only temporary lane closure and control of traffic. This one lane construction, even though desirable in regard to maintaining traffic flow, does pose an additional problem. The longitudinal joint at centerline often becomes a maintenance problem. The objective of this research project is to identify construction procedures that will provide an improved centerline joint.

Asphalt cement concrete pavement recycling, Cass and Montgomery Counties : final report for Iowa DOT project HR-1018, Federal Highway Administration demonstration project no. 39, contract no. DOT-FH-15-336, 1986

This demonstration project consisted of three adjacent highway resurfacing projects using asphalt cement concrete removed from an Interstate highway which had become severely rutted.

Evaluation of control devices for asphalt pavement recycling operations : summary report for research project HR-188, 1982

The objective of the research project was to seek acceptable solutions to the air pollution problem created in the asphalt recycling process using modified conventional equipment.