@article{mocelin_isied_alvis_kusam_underwood_kim_castorena_2023, title={Laboratory Performance Evaluation of Alternative Approaches to Incorporate Recycled Binder Availability into Mixture Design Procedures}, volume={2677}, ISSN={0361-1981 2169-4052}, url={http://dx.doi.org/10.1177/03611981231161601}, DOI={10.1177/03611981231161601}, abstractNote={ There is currently uncertainty in how to properly account for partial recycled binder availability within asphalt mixture design procedures so that content of recycled asphalt materials (RAM) can be maximized while still achieving good performance. This study evaluates and compares two alternative approaches to consider partial availability in mixture design: availability adjusted mix design (AAMD) and corrected optimum asphalt content (COAC). The AAMD method revises the calculation of volumetric properties by considering unavailable binder as part of the bulk aggregate volume and uses the RAM gradation to design the aggregate structure. In the COAC method, a mixture is first designed following the conventional Superpave procedures and then a specified increase to the virgin asphalt content is made. Two “control” mixtures containing RAM are evaluated that were originally designed according to the standard Superpave method. Alternative designs were prepared according to the COAC and AAMD methods while maintaining the RAM content in the respective control mixture. Baseline virgin mixtures and one mixture designed following the AAMD method with higher reclaimed asphalt pavement (RAP) content were also prepared. The cracking and rutting performance of the resultant mixtures was evaluated. The results show that the AAMD and COAC approaches lead to an improved cracking performance compared with the control mixtures even for the mixture designed with AAMD at a higher RAP content. However, the mixture designs prepared according to the COAC method presented increased rutting whereas the AAMD mixtures remained at the same level as their respective control mixture. }, number={10}, journal={Transportation Research Record: Journal of the Transportation Research Board}, publisher={SAGE Publications}, author={Mocelin, Douglas Martins and Isied, Mayzan Maher and Alvis, Maria Carolina Aparicio and Kusam, Abhilash and Underwood, B. Shane and Kim, Y. Richard and Castorena, Cassie}, year={2023}, month={Apr}, pages={519–533} } @article{yadav_kusam_tayebali_2021, title={Evaluating Moisture Damage Using Impact Resonance Test}, volume={49}, ISSN={["1945-7553"]}, DOI={10.1520/JTE20200372}, abstractNote={Abstract Moisture damage in asphalt mixtures has been a major cause for premature failure of asphalt pavements for decades. Although a lot of research has been done and many test methods have been developed to evaluate moisture damage in asphalt mixtures, not much research has been done on the use of nondestructive testing techniques to evaluate moisture damage in asphalt mixtures. The impact resonance (IR) test is a nondestructive test that is used to determine material properties like dynamic elastic modulus. The IR test on asphalt mixtures is done on a thin-disk specimen (150-mm diameter and 25-mm thickness). In this study, the IR test was used to assess moisture damage in asphalt mixtures by determining the resonant frequency of asphalt mixture samples in the unconditioned and moisture conditioned state. The relative reduction (ER) in dynamic elastic modulus was calculated as the ratio of the resonant frequency of conditioned and unconditioned specimens from the IR test, which was used to evaluate moisture damage. Moisture sensitivity of the asphalt mixtures was also determined by the tensile strength ratio (TSR) test. Two different moisture conditioning procedures were used for both the IR test and TSR test—modified AASHTO T 283 (Standard Method of Test for Resistance of Compacted Asphalt Mixtures to Moisture-Induced Damage) and Moisture Induced Stress Tester (MIST) conditioning. Six different mixtures from three different aggregate sources were used in this study. A good correlation was observed between TSR values from the TSR test using both conditioning procedures and the ER values from the IR test using both conditioning procedures for the asphalt mixtures used in this study. This study shows that the IR test can be used to evaluate moisture damage in asphalt mixtures. This study also explored the effects of various parameters such as support condition, impact source, and impact location on the resonant frequency from the IR test.}, number={6}, journal={JOURNAL OF TESTING AND EVALUATION}, author={Yadav, Shivpal and Kusam, Abhilash and Tayebali, Akhtarhusein A.}, year={2021}, month={Nov}, pages={4118–4134} } @article{rashetnia_kusam_yadav_pour-ghaz_tayebali_2022, title={Quantifying moisture damage in asphalt concrete using axisymmetric flexural vibration technique}, volume={23}, ISSN={["1477-268X"]}, DOI={10.1080/10298436.2020.1757671}, abstractNote={ABSTRACT The Tensile Strength Ratio (TSR) test is commonly used to quantify the moisture susceptibility of asphalt mixtures. This test method is based on the indirect tensile strength, which is not a fundamental property and hence cannot be used in the asphalt mixture design process. Therefore, alternative test methods that use a fundamental property to quantify moisture sensitivity of asphalt mixtures are needed. This study investigates if the linear impact resonance shift and frequency spectrum bandwidth changes measured using Axisymmetric Flexural Vibration (AFV) technique can be used to quantify moisture damage. This test enables calculation of the dynamic elastic modulus of the disk, based on measured resonance frequency as well as quantification of vibration energy dissipation in the specimens based on the change in bandwidth of frequency spectrum. AFV test is used to quantify moisture damage susceptibility of asphalt mixture specimens with different moisture conditioning levels and different mixture designs. The results of the AFV test are compared with the TSR test. Also, the sensitivity of the AFV test to quantify the effect of thixotropic aging due to storage and temperature are discussed. The results show that the AFV technique can successfully quantify moisture damage and the effect of aging and temperature change.}, number={3}, journal={INTERNATIONAL JOURNAL OF PAVEMENT ENGINEERING}, author={Rashetnia, Reza and Kusam, Abhilash and Yadav, Shivpal and Pour-Ghaz, Mohammad and Tayebali, Akhtarhusein}, year={2022}, month={Feb}, pages={523–535} } @article{kusam_malladi_tayebali_khosla_2017, title={Laboratory Evaluation of Workability and Moisture Susceptibility of Warm-Mix Asphalt Mixtures Containing Recycled Asphalt Pavements}, volume={29}, ISSN={["1943-5533"]}, DOI={10.1061/(asce)mt.1943-5533.0001825}, abstractNote={AbstractWarm mix asphalt (WMA) and recycled asphalt pavements (RAP) are two popularly used sustainable technologies in pavement industry. Because RAP materials contain aged binder, its use is limit...}, number={5}, journal={JOURNAL OF MATERIALS IN CIVIL ENGINEERING}, author={Kusam, Abhilash and Malladi, Haritha and Tayebali, Akhtarhusein A. and Khosla, N. Paul}, year={2017}, month={May} }