Moisture Damage in Asphalt Concrete

Moisture Damage in Asphalt Concrete
Author: Russell G. Hicks
Publisher: Transportation Research Board
Total Pages: 104
Release: 1991
Genre: Technology & Engineering
ISBN: 9780309049245

This synthesis will be of interest to pavement designers, construction engineers, maintenance engineers, and others interested in avoiding or limiting moisture damage in asphalt concrete. Information is provided on physical and chemical explanations for moisture damage in asphalt concrete, along with a discussion of current practices and test methods for determining or reducing the susceptibility of various asphalt concrete components and mixtures to such damage. Moisture damage in asphalt concrete is a nationwide problem which often necessitates premature replacement of highway pavement surfaces. This report of the Transportation Research Board describes the underlying physical and chemical phenomena responsible for such damage. Current test methods used to determine the susceptibility of asphalt concretes, or their constituents, to moisture damage are described and evaluated. Additionally, current practices for minimizing the potential for moisture damage are examined.

Development of Simple Performance Tests Using Laboratory Test Procedures to Illustrate the Effects of Moisture Damage on Hot Mix Asphalt

Development of Simple Performance Tests Using Laboratory Test Procedures to Illustrate the Effects of Moisture Damage on Hot Mix Asphalt
Author: Jason Bausano
Publisher:
Total Pages: 0
Release: 2006
Genre: Pavements, Asphalt
ISBN:

It has been extensively documented since the late 1970's that moisture damage occurs in hot mix asphalt (HMA) pavements. A variety of test methods are available that test an HMA's ability to resist moisture sensitivity. There are also some test methods that look at an asphalt binder's moisture susceptibility. The current test method for detecting moisture sensitivity in HMA is American Association of State Highway and Transportation Officials (AASHTO) T283: Resistance of Compacted Bituminous Mixture to Moisture-Induced Damage. Inclusion of this test method in Superpave did not consider the change in specimen size from 100mm to 150mm nor difference in compaction method. The procedures in AASHTO T283 consider the loss of strength due to freeze/thaw cycling and the effects of moisture existing in specimens compared to unconditional specimens. However, mixtures do not experience such a pure phenomenon. Pavements undergo cycling of environmental conditions, but when moisture is present, there is repeated hydraulic loading with the development of pore pressure in mixtures. Thus, AASHTO T283 does not consider the effect of pore pressure, but rather considers a single load effect on environmentally conditioned specimens. This report develops moisture susceptibility procedures which would utilize repeated loading test devices (dynamic modulus or asphalt pavement analyzer) of specimens in saturated conditions and be compared to unconditioned specimens in a dry test environment. In addition to HMA mixture testing, a modified dynamic shear rheometer will be used to determine if an asphalt binder or mastic is moisture susceptible. Moisture susceptible criteria was developed using the dynamic complex modulus, asphalt pavement analyzer, and dynamic shear rheometer. Evaluation of AASHTO T283 for 150mm Superpave Gyrtaory compacted specimens is also detailed in this report along with a new criterion.

Improved Conditioning and Testing Procedures for HMA Moisture Susceptibility

Improved Conditioning and Testing Procedures for HMA Moisture Susceptibility
Author: Mansour Solaimanian
Publisher: Transportation Research Board National Research
Total Pages: 84
Release: 2007
Genre: Technology & Engineering
ISBN:

Explores whether combining the environmental conditioning system with the simple performance test would provide a superior procedure for determining the moisture susceptibility of hot-mix asphalt (HMA).

Rheometry of Pastes, Suspensions, and Granular Materials

Rheometry of Pastes, Suspensions, and Granular Materials
Author: Philippe Coussot
Publisher: John Wiley & Sons
Total Pages: 311
Release: 2005-06-14
Genre: Technology & Engineering
ISBN: 0471720569

A comprehensive examination of rheometry theory and its practical applications This publication enables readers to understand and characterize the flow properties of complex fluids and, with this knowledge, develop a wide range of industrial and consumer products. The author fills a gap in the current literature by presenting a comprehensive description of the rheological behavior of pastes, suspensions, and granular materials and by offering readers the rheometrical techniques needed to effectively characterize these materials. With his extensive experience in both academic and industrial research, the author is able to take the field to a new level in: * General schematic classification of the behavior of pastes,suspensions, and granular materials * Systematic review, analysis, and quantification of experimental problems with complex fluids * Insight into the flow behavior of complex fluids gained through the most recent discoveries and research techniques * Comprehensive rheometrical analysis of data obtained from research across a broad range of industries In addition to gaining a thorough understanding of the theory underlining rheometry, readers discover its many practical applications. Throughout the publication, specific examples are provided that illustrate how theory is applied, including examples involving food, civil engineering, cosmetics, pharmaceuticals, paper coatings, paint and ink, ceramics, sewage sludges, granular materials, and natural materials. In summary, this publication provides a comprehensive review of the behavior of pastes, suspensions, and granular materials as well as detailed analysis of rheometrical techniques. Everything needed to determine the behavior and movement of complex fluids is provided. It is, therefore, a recommended resource for rheologists, engineers, and researchers, as well as students who deal with complex fluids in product formulation, quality and process control, and process plant design.

Effect of Testing Conditions on Laboratory Moisture Test for Asphalt Mixtures

Effect of Testing Conditions on Laboratory Moisture Test for Asphalt Mixtures
Author: Junyan Yi
Publisher:
Total Pages: 12
Release: 2016
Genre: Aging
ISBN:

Moisture damage is one of the major causes of premature failure in asphalt pavements, and it also accelerates the severity of other distresses. To date, no moisture test has been widely accepted that is reliable and practical in predicting the field moisture performance of the asphalt mix during the design stage. One reason is because the sample conditioning methods cannot represent the field conditions, resulting in inconsistent results with the field performance of some mixtures. Taken into account this concern, this paper investigates how different testing conditions, including sample preparation, moisture saturation, and loading methods, can affect the results of laboratory moisture tests. In conclusion, it is found that the degree of vacuum pressure for achieving moisture saturation and air voids distribution has a significant impact on the moisture testing results. Multiple freeze-thaw cycles have a limited effect on the variation of mechanical performance (i.e., compressive dynamic modulus). If one or several freeze-thaw cycles are to be used in a moisture test, the effect of aging should be considered. It is recommended that a sample without coring and cutting should be used for a moisture test as the coring and cutting process is found to change the air voids distribution, i.e., the percent of connected air voids, thus making the sample not representative to the field condition. Finally, the moisture test results are more sensitive under tension mode than under compression mode.

Evaluation of Test Methods to Predict Moisture Damage in Asphalt Concrete

Evaluation of Test Methods to Predict Moisture Damage in Asphalt Concrete
Author: Bradley J. Bruce
Publisher:
Total Pages: 0
Release: 1990
Genre: Pavements, Asphalt
ISBN:

The actual moisture susceptibility of 10 bituminous mixtures placed in the field was compared to the moisture susceptibility that was predicted during the laboratory evaluation of the same mix design. Laboratory mixtures were evaluated using the modified Lottman procedure and the Root-Tunnicliff procedure, in addition to routine moisture susceptibility testing which includes immersion compression testing. After two years, cores were taken from the field projects. The condition of the cores and their present susceptibility to moisture damage were determined by performing modified Lottman and Root-Tunnicliff testing. A feature of the evaluation process was the use of the ACMODAS program to predict the remaining service life of the plant mix cores.

Implementation of Laboratory Conditioning and Testing Protocol to Evaluate Moisture Susceptibility of Asphalt Mixtures

Implementation of Laboratory Conditioning and Testing Protocol to Evaluate Moisture Susceptibility of Asphalt Mixtures
Author: Erdem Coleri
Publisher:
Total Pages: 0
Release: 2023
Genre: Asphalt
ISBN:

Moisture damage in asphalt mixtures can cause early cracking and rutting failures due to the internal damage accumulated by the high internal pore pressures created at the aggregate-binder interface and/or within the binder phase by heavy traffic loads. Due to the high precipitation levels and frequent rain events, distresses originating from moisture damage are commonly observed on roadways in Oregon. ODOT has been mostly using hydrated lime to combat distresses related to moisture damage at the mixture level, while the effectiveness of new chemical anti-strips and warm-mix technologies has also started to be investigated. However, a reliable moisture conditioning method and moisture susceptibility test need to be developed and implemented for Oregon to determine the possible long-term impact of several new additive technologies on pavement longevity. Roadway geometry, asphalt layer density, construction of proper superelevation on the roadway for effective water removal, and functioning drainage facilities can be considered to be the other important factors that control moisture-related failures on roadways. Based on the comprehensive literature review and the results of the laboratory investigations, this study recommends the use of a colorimeter in conjunction with the current AASHTO T 283 (2014) method to determine the adhesion and cohesion-related moisture susceptibility. According to the laboratory test results, vacuum saturation is able to create significant moisture damage in the asphalt microstructure, and no other conditioning method needs to be adapted to replace the vacuum saturation method. Developed tools and test procedures are expected to help ODOT identify the benefits of recent additive technologies that are being developed to combat moisture damage of asphalt mixtures.