Fraunhofer Develops Sensor Mats for Road Condition Monitoring

The Fraunhofer Institute for Wood Research has introduced an innovative sensor system that integrates flax fiber mats into asphalt roads to monitor their structural integrity. This technological advancement aims to identify internal damages such as cracks and potholes in real-time, potentially revolutionizing road maintenance.

Traditionally, assessing the condition of asphalt roads requires costly and invasive methods, including drilling boreholes that can damage the road surface. The researchers from the Wilhelm-Klauditz-Institut (WKI) have devised a solution by embedding sensor mats within the asphalt. These mats are composed of woven flax fibers that incorporate 1 mm thick conductive sensor wires, allowing for continuous monitoring.

The WKI scientists utilize a dual-gripper weaving machine to produce sensor mats that can be 50 cm wide and of any length, ensuring versatility in application. The strength of the material is enhanced by using high-tensile yarns, preventing any unwanted structural disruptions within the asphalt during installation and throughout its lifespan. This durability enables the sensor mats to withstand both environmental factors and the heavy loads typically experienced by road surfaces.

The sensors work by measuring changes in resistance within the conductive wires, which occur as a result of damage to the asphalt layer. These data points are then analyzed by software that employs artificial intelligence (AI). This software not only identifies existing damages but also forecasts potential future issues, enabling road authorities to address problems proactively and economically.

Data collected from the sensor mats will be made available through an online platform, where it will be presented in an accessible format for various stakeholders, including government agencies, residents, companies, and road users potentially affected by construction activities.

Initial laboratory tests have shown promising results, and practical trials are underway on a road in an industrial area equipped entirely with the sensor material. These measurement points are already capturing data on resistance changes with remarkable precision, allowing for accurate readings of axle loads when heavy vehicles pass over them. Further testing will confirm whether these sensors can reliably indicate road damage.

This research initiative is funded by the Federal Ministry of Transport and is a collaborative effort involving Uhlig & Wehlig GmbH, AS+BE Asphalt- und Betonstraßenbau GmbH, Time4Innovation UG, and the universities of Magdeburg-Stendal and Hanover.