Advanced Diagnostic of Subsurface Decay in Rigid Airfield Pavements: A Signal-Processing-Enhanced GPR Approach

The condition of airfield pavements is critical for ensuring the safety and efficiency of airport operations. Compared with highway pavements, runways and taxiways are subjected to heavier and more repetitive dynamic loading, which can lead to complex subsurface decay mechanisms that are not easily detected through surface inspection. Among these, mud pumping is particularly damaging, as it accelerates the deterioration of rigid concrete slabs.

Mud pumping occurs when water accumulates at the interface between a concrete slab and its supporting layers. Under repeated loading, a slurry of water and fine particles is expelled through joints and cracks, leading to subsurface voids, loss of support, and eventual structural failure. Performing an advanced diagnostic of these features at an early stage is essential for effective maintenance [1].

This study presents a collaborative investigation between academia and Heathrow Airport to assess the capability of Ground Penetrating Radar (GPR) as a primary non-destructive tool for diagnosing early-stage pavement decay. While GPR provides high-resolution subsurface data, the interpretation of these data remains a key challenge, particularly in complex pavement environments.

To address this, the study emphasises signal-processing-enhanced approach to improve data interpretability [2]. By enhancing the visibility and contrast of subsurface responses and analysing signal behaviour beyond conventional time-domain representations, the approach aims to extract more reliable diagnostic indicators of moisture accumulation, void development, and layer interfaces’ misalignment.

The results demonstrate that improving data interpretation is essential for the accurate diagnosis of decayed pavement states. This supports a shift toward more proactive, data-driven maintenance strategies for airfield infrastructure.

References

[1] Maser, K. R. (2013). Use of GPR for Subsurface Pavement Investigations of 23 Airports in South Carolina, Proceedings Ninth International Conference on BCRRA, Vol 1.

[2] Benedetto, A., Tosti, F., Bianchini, L., & D’Amico, F. (2018). An Overview of Ground-penetrating Radar Signal Processing Techniques for Road Inspections, Vol. 32, 201-209.