Preventing the risk of accidents through the simulation of GPR-based pavements damage inspection

It is well-known that road safety issues are closely related both to pavement damages and surface unevenness. To prevent the most critical impacts on human lives, many efforts should be addressed towards the application of effective strategies and techniques for road network maintenance.\ud In that respect, ground-penetrating radar (GPR) can be considered as one of the most flexible non-destructive tools, for controlling both the physical and geometrical properties of pavements.\ud On the other hand, the evaluation of road pavement operability is traditionally carried out on the basis of standardized comprehensive indexes, as a result of visual inspections or measurements. Such analyses arise from superficial assessments of the pavement conditions, wherein only the effects and not the causes of damages have been considered. In this regard, GPR has proven to be over the past decades both an effective and efficient technique for monitoring the pavement conditions.\ud In this study, one of the main causes (i.e., local collapses of the subgrade) of surface damage have been analyzed through simulation tests on the basis of the finite-difference time-domain (FDTD) method, in order to yield synthetic data sets. In particular, the GprMax 2D numerical simulator for GPR has been used on three different types of flexible pavements to retrieve the numerical solution of Maxwell’s equations in the time domain. Therefore, the electromagnetic response from the simulations has been evaluated, case by case.\ud Results show the high potential of GPR in detecting the causes of such damage