Cracking resistance assessment of emulsified asphalt cold recycled mixtures using modified Paris law

Emulsified asphalt cold recycled mixtures are workable and cost-effective but suffer from poor cracking resistance, particularly under temperature fluctuations and freeze–thaw conditions in cold regions. This study employs the modified Paris law to model crack propagation at both laboratory and pavement scales. Results show that a simulation combining the extended finite element method with semi-circular bending (SCB) fracture tests accurately predicts crack growth. A pavement crack propagation model incorporating pre-existing base cracks was developed to evaluate the cracking resistance of mixtures intended for cold-region applications. Simulations under diverse loading conditions reveal that the coupling of thermal stress and symmetric loading represents the most critical scenario triggering crack propagation in the recycled layer. Notably, excellent consistency is achieved among experimental SCB crack growth data, SCB simulation results, and full-scale pavement calculations, validating the proposed approach for practical engineering use.