A critical review of monotonic loading tests to evaluate rutting potential of asphalt mixtures

Balanced mix design (BMD) is gaining popularity among highway agencies in the United States. That is because such concept allows innovations to be responsibly incorporated into asphalt mixtures, and quantifies the quality, where the volumetric properties and gradations alone cannot differentiate asphalt mixture performance. Additionally, such concept is expected to increase the durability and performance of asphalt mixtures. The BMD concept constitutes a series of different design alternatives and requires a suite of laboratory-based performance tests to be conducted on an asphalt mixture during the mixture design and production stages, thus making performance tests a critical part of the concept. Several monotonic loading test methods have emerged and been standardized to evaluate the cracking potential of asphalt mixtures in a straightforward manner. Similar monotonic loading tests have also been considered for evaluating the rutting potential of asphalt mixtures. This review provides researchers, transportation agencies, and practitioners with the state-of-art information on the use of monotonic loading tests to assess the rutting potential of asphalt mixtures, with particular emphasis given on the indirect tensile test (IDT) at high temperatures. The test methods documented in this work show the versatility of such tests in screening the rutting potential of asphalt mixtures. A set of considerations are also provided and discussed for implementation prospects of a monotonic loading rutting test.

Automated summary

Balanced mix design (BMD) is becoming popular in US highway agencies as it allows responsible incorporation of innovations into asphalt mixtures and improves their durability and performance. Monotonic loading test methods, particularly the indirect tensile test (IDT) at high temperatures, are effective in assessing the cracking and rutting potential of asphalt mixtures.