Assessment of road condition and the supporting ground is essential to allow the efficient long-term functioning of any transport network. Intrusive investigations provide vital information, but are costly, time consuming and have the limitation that data is discrete in a highly variable environment.
Existing road structures are subject to a variable degree of maintenance and re-construction. Their internal structure can be very complex, containing several layers and sections of material of different ages and condition.
To leverage roadways structural reliability and extend their usable lifetime, it is important to closely monitor their structural conditions effectively and efficiently. Early and accurate detection, localization and assessment of damages or defect in pavements are of great values for scheduling maintenance and rehabilitation activities and can significantly reduce the damage progression and maintenance costs. To achieve these goals, developing and applying appropriate tools and measurement methodologies are indispensable.
For roadway asphalt pavement, the in-situ density is regarded as one of the most important controls to ensure that a pavement being placed is of high quality because it is a good indicator of future performance. In-situ density is frequently assessed utilizing three methods: cores, nuclear density gauge measurements or non-nuclear density gauge measurements. However, these methods are destructive; only provide density readings at discrete sampling locations. Moreover, they are slow and may cause disturbance to road traffic. These drawbacks limit their applications for pavement profile assessment during the roadway construction and lifetime maintenance.
Among all NDT techniques, GPR is one of the most important tools enabling subsurface structural characterizations. The state-of-the-art in the inspection of pavements is the use of 3D GPR arrays that allow to extend the analysis also in the traverse direction of the road. These perpendicular cross-sections provide very useful information to road engineers and maintenance crews.

EVEREST GEOPHYSICS applies advanced processing techniques to study the condition of the wearing course