Fracture Behavior of Modified Asphalt Mixtures Under Varying Temperature and Notch Depth: Experimental Investigation and XFEM Simulation

ABSTRACT The combined effects of temperature, notch depth, and binder modification on asphalt fracture behavior remain insufficiently understood, particularly when experimental characterization is combined with crack‐propagation modeling. This study addresses this gap through a systematic SCB investigation of unmodified and modified asphalt mixtures at −20°C, 0°C, 20°C, and 40°C using 10‐, 20‐, and 30‐mm notch depths. Five modifiers SBS, Enprene 611, Enprene 701, crumb rubber, and Elvaloy–PPA were evaluated at different dosages, whereas XFEM models were developed in Abaqus to simulate fracture and crack propagation. Increasing temperature transformed the response from brittle to ductile, whereas deeper notches consistently reduced peak load. Binder modification generally enhanced fracture performance, with Enprene 611 and SBS providing the greatest improvements. XFEM reproduced pre‐peak and peak responses reasonably well but showed larger deviations during post‐peak softening at elevated temperatures. The findings establish the coupled influence of temperature, notch geometry, and modification on asphalt fracture and identify key limitations of the numerical post‐peak simulations.