During the BEPROACT Mid-Term Event in Eindhoven, the MESAS Traffic Speed Deflectometer (TSD) was successfully demonstrated and presented to project partners. The MESAS framework, developed within the BEPROACT project, was introduced by Léo Sotto and Mehdi Kalantari, highlighting how the system supports data-driven and proactive pavement management. In preparation for and following the event, Alfred Meyer and Yannick Langer carried out measurements covering hundreds of kilometres of the Dutch motorway network. The collected data will be further analyzed and actively used within this transnational BEPROACT project.
BEPROACT partner BASt (Federal Highway and Transport Research Institute) operates MESAS, an innovative multifunctional assessment tool for the structural evaluation and design of pavements. MESAS is designed to assess pavement condition efficiently at traffic speed, supporting proactive and data-driven asset management at network level.
At the core of MESAS is the Traffic Speed Deflectometer (TSD), a fast-moving bearing capacity measurement system installed on an articulated vehicle. The single axle of the semi-trailer applies a static load of approximately ten tonnes to the pavement, while dynamic axle loads generated during driving are continuously recorded. Using Doppler laser sensors, MESAS measures pavement deformation velocity without direct contact, both in front of and behind the load axle. These measurements allow precise calculation of pavement deflections and enable in-depth analysis of structural bearing capacity.
MESAS is designed for measurements at speeds of up to 80 km/h, allowing data collection “within the flow of traffic” and minimizing disruption. The system is therefore particularly suited for large-scale network-level assessments. Measurements are currently carried out on asphalt pavements, while applications on concrete pavements are subject to further development.
In addition to deflection measurements, MESAS is equipped with Ground Penetrating Radar (GPR) using a 2 GHz horn antenna. This enables non-destructive detection of layer thicknesses and identification of inhomogeneities within pavement structures and subgrade layers.
A second-generation pavement profile scanner (PPS+) is installed at the rear of the MESAS vehicle. This laser-based system records transverse evenness and surface images across the full lane width, supporting further analysis of pavement geometry and longitudinal evenness. Additional sensors, including accelerometers, complement the measurement system and enrich the dataset.
By combining structural, geometric and subsurface data in one integrated measurement platform, MESAS provides a powerful foundation for proactive pavement management. Within BEPROACT, MESAS demonstrates how advanced sensing technologies and real-time data can support smarter maintenance decisions, extend asset lifespans and strengthen the resilience of Europe’s road infrastructure.