Although some types of geosynthetics have been recognized for their great benefits in preventing water infiltration into the pavement system underlying layers and to dissipate strain energy in a cracked rehabilitated pavement, the evidence of this contribution is extremely difficult to quantify. With the advance in electromagnetic techniques, measuring and monitoring the moisture content in pavement systems appears feasible, and geosynthetics benefits as moisture barrier can be verified. To investigate the performance of a geocomposite membrane (a low modulus polyvinyl chloride [PVC] layer sandwiched between two nonwoven geotextiles), two sections at the Virginia Smart Road were instrumented and constructed to quantify its effectiveness as a moisture barrier and as a strain energy absorber.

The moisture variation in the subbase aggregate layer over different precipitations was continuously monitored using time domain reflectometry. Ground penetrating radar was also periodically used to monitor water movement in the pavement sections. Results of ground penetrating radar (GPR) surveys and time domain reflectometer (TDR) moisture sensors validated the effectiveness of the geocomposite membrane in abating water infiltration into the subbase layer even in the event of heavy rain. The potential of the geocomposite membrane to mitigate the reflection of cracks has been theoretically investigated using the finite element (FE) analysis approach. A model was developed to simulate a cracked pavement structure and predict the crack propagation. Four contour lines were simulated around the crack to calculate the path-independent integral. Analysis of results indicates that the geocomposite membrane is effective in dissipating a large amount of energy around the cracked region. This has been verified by field cores and falling weight deflectometer (FWD) data analysis. The study showed that a soft interlayer system might increase the number of cycles for crack initiation by several orders of magnitude.