Book Description

Fatigue cracking is one of the critical distress modes in asphalt pavements. Accurate prediction and evaluation of fatigue performance are crucial to extending the service life of asphalt mixtures. Naturally, laboratory testing methods for fatigue characterization are time-consuming and require sophisticated procedures. Any effort to improve the speed and quality of the information gained from laboratory fatigue tests is valuable. This research work presents the results of a study investigating the possibility of implementing a new approach to characterize asphalt mixture fatigue behavior. This new approach includes cyclic tests run on cylindrical asphalt specimens in three-point beam mode (herein referred to as three-point bending cylinder (3PBC) geometry). Timoshenko beam theory along with the viscoelastic continuum damage (VECD) theory was implemented to model the mechanical response of the specimens. An excellent correlation between the results of 3PBC tests and uniaxial push-pull fatigue tests were observed. The 3PBC setup possesses the most advantages of uniaxial push-pull tests and includes more advantages such as not requiring a saw to cut the ends of the sample, not requiring gluing operation (and the gluing jig) and the possibility of estimating Poisson's ratio from the data. The proposed 3PBC approach was evaluated through laboratory tests conducted on various asphalt mixtures with varying binder types, mix components, and volumetric properties. The approach proposed herein was validated through finite element analysis. In addition, ruggedness evaluation of the 3PBC testing approach through varying factors and their levels were investigated and presented.