Evaluating the Effects of High RAP Content and Rejuvenating Agents on Fatigue Performance of Fine Aggregate Matrix through DMA Flexural Bending Test

Abstract

High percentage reclaimed asphalt pavement (RAP) is prevailing in pavement engineering for its advantages in sustainability and environmental friendliness, however, its fatigue resistance remains a major concern. Fine aggregate matrix (FAM) is a crucial part in the fatigue resistance of asphalt mixtures with high RAP content. Hence, the linear amplitude sweep (LAS) test of FAM has been developed to study the fatigue resistance of asphalt mixtures. However, the torsional loading mode of the LAS test with a dynamic shear rheometer (DSR) is a limitation to simulate traffic load. In this paper, an alternative LAS test for FAM with high RAP content was proposed. Beam FAM specimens were tested using a dual-cantilever flexural loading fixture in a dynamic mechanical analyzer (DMA). To investigate the influence of RAP content and the rejuvenating agent (RA), four kinds of FAM mixes were tested with this method to study their fatigue resistance. The test results suggested that the repeatability of this alternative approach was reliable. A fatigue failure criterion based on maximum C × N was defined. Then, fatigue life prediction models based on viscoelastic continuum damage (VECD) analysis were established according to the LAS test results and validated by a strain-controlled time sweep (TS) test. It turned out that as RAP content increased, the modulus of FAM would be significantly raised, accompanied with a drop in the phase angle. The fatigue life of FAM would be greatly shortened when the RAP binder replacement rate reached 50%. Adding RA could considerably improve the dynamic properties of FAM mixes with high RAP content, resulting in a decrease in modulus, increase in phase angle and elongating fatigue life, but could not recover to the level of virgin binder.

Performance Characterization of Hot Mix Asphalt with High RAP Content and Basalt Fiber

“…Tremendous studies have been conducted to investigate the effect of RAP on the performance of asphalt mixtures, especially on cracking resistance. Zhou's research [12] pointed out that the use of RAP increased the cumulative rate of fatigue damage, subsequently resulting in shortened fatigue life of asphalt mixtures, which has been proved by some other investigations [13,14]. The use of RAP also further diminished the low-temperature property of asphalt mixtures, and commonly made the mixtures prone to thermal cracking [9,15], especially in cold regions.…”

Experimental Analysis of Hot-Mix Asphalt (HMA) Mixtures with Reclaimed Asphalt Pavement (RAP) in Railway Sub-Ballast

“…The results reveal that S’m increases with the RAP content due to the higher elastic response. Nevertheless, high values of S’m could result in the fragile behavior of mixtures and low fatigue resistance [ 75 ]. On the other hand, the RAP content does not affect the reduction of S’m due to the temperature increase.…”

Long-Term Performance Evolution of RIOHTrack Pavement Surface Layer Based on DMA Method

“…This study focuses on RIOHTrack's three major categories of six types of pavement structure surface layers, namely, semi-rigid base asphalt surface layer (STR1, 3), flip-chip structure (STR10, 12), and thick asphalt surface layer structure (STR18, 19). The surface layer material of STR1/3 and 10/12 is AC-13, and that of STR18/19 is SMA-13.…”