Finite element modelling of flexible pavements on soft soil subgrades

The effect of tyre pressure, wheel configuration and axle load variations of a transportation truck, on structural performance of a flexible road pavement with thin asphalt surfacing layer and soft peat soil subgrade was evaluated using the finite element method. The pavement structure was modelled as two-dimensional four-layer stratum using ANSYS/ED finite element suite. The pavement model was subjected to cyclic loadings to simulate three levels of truck wheel loads at four tyre inflation pressures of 350,490,630 and 770 kPa. Results from the model were verified using in situ full-scale test data. Model comparisons with measured full-scale test data were in good agreement, with coefficient of determination (R²) ranging from 0.66 to 0.92. Therefore, for known pavement material characteristics and tyre-pavement contact regime, finite element method could be used to efficiently estimate the potential distress.