The Environmental Conditioning System (ECS) was designed to evaluate the
water sensitivity of asphalt concrete mixtures. The ECS subjects asphalt concrete specimens to a series of conditioning cycles including water flow, elevated and/or lowered temperature, and repeated axial loading. The purpose of this research was to: (1) evaluate the ECS...
Asphalt concrete pavement is subjected to several damaging actions from traffic
loads, water (from precipitation and/or groundwater sources), and temperature. The
durability of the asphalt-aggregate mixture, its ability to withstand these damaging
actions for long periods, is a very important engineering property. While the durability
of the asphalt-aggregates mixture depends...
Moisture damage has long been recognized as one of the most
critical factors influencing the performance of asphalt concrete (AC)
pavements. This moistureinduced damage occurs from either the
physical separation of the asphalt film from the aggregate or the
softening of the asphalt binder within the AC mixture in the...
Environmental factors such as temperature, air, and water can have a profound
effect on the durability of asphalt concrete mixtures. In mild climates where good
quality aggregates and asphalt cement are available, the major contribution to
deterioration may be due to traffic loading and the resultant distress is manifested
in...
The research undertaken consisted of the study of three topics
affecting the performance of asphalt concrete mixtures, that is, mixing
moisture, oxidative aging and higher tire pressures and axle loads.
This thesis presents the findings of the research comprising these
three topics.
In the first study, the effects of mixing...
In 1987, Congress authorized a 5 year $150 million dollar research program called
the Strategic Highway Research Program (SHRP). SHRP was divided into four major
areas, including the asphalt research program. The asphalt research program was divided
into six major research contracts, one such contract, SHRP-003A was called Performance
Related...
Polymer modified asphalts have recently been the focus of much
attention in the U.S. due to claims that polymer additives will
lengthen the life of an asphalt pavement. Much of the published
research on this topic has been concentrated on the effects of
polymer modifiers on binder and mixture properties....
Testing of asphalt binders and asphalt-aggregate mixtures using dynamic
mechanical analysis is becoming popular with improvements in high-speed
computers, precision equipment, and computer software. Researchers are trying
to describe the behavior of asphalt binders and asphalt-aggregate mixtures in
terms of their time- and temperature-dependent linear viscoelastic behavior.
The objectives of...