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Conventional index-based testing of asphalt mixtures cannot accurately capture local deformation in a sample, limiting the usage of standard test measurements. The non-contact-based measurements proved effective to capture local deformation fields. This study aimed to capture the fatigue and thermal cracking behaviour of fiber-reinforced asphalt mixture (FRAM) by utilising digital image correlation (DIC). One binder (PG76-22), a diabase aggregate and three fibers (polyolefin/ aramid fibers (PFA) at 0.05% dosage and Sasobit-coated aramid fibers at 0.01% and 0.02% dosage) were used to prepare a total of four mixtures (one control and three FRAM). All these mixtures were produced at a local batch plant following manufacturer-recommended mixing methods. DIC analysis was performed for three-point bending beam (3PB) and disk shape compact tension (DCT) tests at intermediate temperature (25°C) and low temperatures of −12°C and −18°C. Based on index values from DCT and 3PB, the thermal and fatigue cracking performance enhancement was not significant. However, DIC analysis showed that, regardless of testing temperature, the crack propagated in a random pattern for FRAM, whereas the crack followed a relatively straight path for the control mix. Finally, based on DIC strain contours, FRAM mixtures exhibit distributed strain over a larger area compared to the control mix. [ABSTRACT FROM AUTHOR]

This study aims to assess the impact of microencapsulated phase change materials (MPCMs) on thermoregulation effect and binders' performance. Accordingly, three MPCMs with melting points 6°C, 28°C, and 37°C were blended with PG 58-28 and PG 64-22 binders at dosages of 5%–20% by binder weight. Subsequently, laboratory experiments were conducted to examine impact on thermoregulation and rheological parameters including enthalpy change, complex modulus, Glover-Rowe parameter, creep stiffness, creep slope, fatigue, and rut factors. The findings showed that increasing MPCMs' dosage in both control binders led to increased enthalpy change, indicating successful thermoregulation and capsules' survival during blending. Rheological investigation depicted increasing complex modulus, creep stiffness and Glover-Rowe parameter in modified binders compared to control binders regardless of MPCMs' thermoregulation range. However, Dynamic shear rheometer and Bending beam rheometer may not adequately capture their thermoregulation impact under steady-state conditions, necessitating use of temperature sweep test to validate influence on complex modulus and phase angle due to their thermoregulation capability. Temperature sweep test showed that within thermoregulation range, MPCMs with melting points 6°C and 28°C showed comparable fatigue resistance to respective control binders up to 10% dosage. Meanwhile, around melting point, MPCM with 37°C melting point enhanced rutting resistance. [ABSTRACT FROM AUTHOR]