Behavior of Transverse Cracks in Continuously Reinforced Concrete Pavement under Environmental Loadings

Continuously reinforced concrete pavement (CRCP) uses longitudinal steel to control transverse cracks, which form naturally to relieve tensile stresses induced by environmental loadings. Previous studies have suggested that such stress relief is highly localized, typically diminishing within approximately 300 mm of a newly formed crack. This study investigates the strain interaction between adjacent cracks using a fully instrumented CRCP section on IH-20 in Sweetwater, Texas. Field measurements demonstrate that the formation of a new transverse crack significantly reduces longitudinal strain in both the steel and the surrounding concrete. Formation of a new crack reduced steel stresses around 24.8 MPa at an existing crack 2.13 m away. This finding provides direct evidence that stress redistribution can extend well beyond the traditionally assumed 300 mm influence zone. Observations also indicate that cracks penetrating the full depth near the pavement edge may transition to partial-depth cracks toward the slab interior and remain stable over time. Adjacent transverse cracking significantly relieves vertical concrete stress at steel depth near an existing crack by approximately 0.67 MPa. This represents roughly 20% of the concrete tensile strength, reducing the potential for horizontal delamination. Monitoring into the second winter season showed a mean crack width increase of about 0.1 mm under comparable thermal conditions (t = 26.99, p < 0.001). This behavior contrasts with the commonly held assumption that stress diminishes progressively over time. Overall, these findings provide a refined understanding of transverse crack behavior in CRCP and support the advancement of mechanistic–empirical pavement performance models.