One of the major objectives in the strategic highway research program project a-003a, performance related testing and measuring of asphalt-aggregate interactions and mixtures, is to develop accelerated performance-related tests for asphalt-aggregate systems that successfully model construction and service conditions. Controlled-stressdiametral fatigue testing was conducted at north carolina state university to evaluate the influence of temperature and mixture variables on fatigue life of asphalt concrete mixtures with rb (mrl code) aggregates. The resilient modulus testing fixture developed by mts systems corporation in accordance with astm d4123 was used with the mts closed-loop servohydraulic system. Diametral fatigue test results plotted on a logarithmic scale of recoverable horizontal deformationand number of cycles to failure showed a good agreement with the historic trend of the fatigue data. The analysis of variance test results indicated that all the factors investigated in this research significantly affected the fatigue performance of asphalt concrete. In summary, the fatigue resistance was improved by increasing asphalt content and reducing air void contents. The effect of temperature on the fatigue performance of asphalt concrete determined by using recoverable horizontal strain was opposite to that determined by using maximum total horizontal strain. Asphalt concrete with a softer binder resulted in longer fatigue life. Furthermore, the temperature susceptibility of asphalt binder had a pronounced effect on the fatigue life of asphalt concrete mixtures. This paper appears in transportation research record no. 1317, Asphalt mixtures: design, testing, andevaluation 1991.
Samenvatting