Three dimensional finite element modelling of pavements subsurface drainage systems

Pavement subsurface drainage systems (PSDS) are designed to drain the entrapped water out of pavement. To investigate the effects of various factors on the performance of PSDS, three dimensional models were developed using the finite element method to simulate the unsaturated drainage process in pavement. The finite element models were calibrated using the field information on outflow, peak flow, layer saturations, and time to drain. Through a series of parametric analyses, the factors that significantly influence the performance of PSDS were screened out, and a set of recommendations were made to improve our current drainage practices.