Thermo-Mechanical Response of Geocell-Reinforced Concrete Pavements: Scaled Model Tests and Finite Element Analyses

This study investigates the thermo-mechanical response of geocell-reinforced concrete pavements through scaled model tests and three-dimensional coupled finite element analyses. Static, cyclic, thermal, and coupled loading tests were conducted to clarify deformation evolution, strain distribution, and damage characteristics of the reinforced structure. The results show that, under static loading, pavement settlement evolves through three stages, namely initial compaction, plastic development, and stabilization, indicating progressive mobilization of geocell confinement. Under thermal loading, slab strain exhibits pronounced spatial and temporal non-uniformity, and the slab centre is identified as the thermally sensitive zone. Under coupled high-temperature and static loading, both strain and settlement show a non-monotonic increase–decrease trend at approximately 1.1–1.3 kN, suggesting a potential threshold for damage initiation. Under cyclic loading, permanent deformation accumulates with load repetitions and is highly sensitive to load amplitude. Numerical results further show that geocell reinforcement reduces the central settlement by 17.4% relative to plain concrete pavement and by 7.6% relative to a doweled pavement, while producing a smoother deflection basin and a more uniform stress distribution. Parametric analyses indicate that the optimum geocell height is approximately one-third of the surface course thickness; beyond this range, the marginal reinforcement benefit decreases. The results demonstrate that geocell reinforcement can significantly improve load transfer, deformation compatibility, and thermo-mechanical stability of concrete pavements.