Dynamic analysis of prestressed pavement over layered unsaturated soils considering groundwater level effects

Climate change and sea level rise can alter groundwater levels in subsurface soils, thereby influencing the performance and durability of pavement structures. This paper explores the steady-state vibration of prestressed concrete pavement over layered transversely isotropic unsaturated soils with different groundwater levels under moving loads. Based on the existing triphasic Biot-type theory, the flexibility coefficients of unsaturated soils are derived using the extended precise integration method, together with boundary and interlayer continuity conditions. These coefficients are then incorporated into the governing equations of the prestressed pavement to obtain dynamic solutions for the pavement with different groundwater levels. After confirming the reliability of the proposed method through result comparison, parametric analysis is conducted to examine the effects of groundwater level, prestress magnitude, and plate thickness on the system’s dynamic behaviour. The calculation results reveal that a lower groundwater level reduces the bending moment and shear force within the pavement. Moreover, applying prestress slightly alleviates stress concentration, while increasing plate thickness provides a more significant relieving effect.