Effect of environmentally friendly transports

Purpose and goal

The goal was to study the effect of heavy vehicles on the structural condition of roads, by evaluating measured performance. Thus, verifying bearing capacity to optimize potential strengthening measures is required for DK4 roads. The project has carried out Continuous Deflection Testing that has compared the results with traditional FWD measurement. A refined assessment of the bearing capacity can enable a larger part of the road network to be used for sustainable transportation, which is a major part of the national goal to reduce the climate impact from the transport sector.

Expected results and effects

BK4 enables more environmentally friendly transportation. Before roads can be accepted for heavier vehicles, an evaluation of the road´s structural condition and needed strengthening is required. Currently, approx. 20% of the strategic road network is permitted for 74-ton vehicles. The study shows that Continuous Deflection Testing (TSD) is a useful method for evaluating the structural conditions and distinguishing parts with low and high load-bearing capacity. Further studies are recommended to consider temperature gradients as well as the moisture content in the road body.

Planned approach and implementation

The project has evaluated two different pieces of equipment for Continuous Deflection Testing, TSD (Greenwood) and Raptor (Dynatest). Measurements have been performed on strong and weak roads. Carried out tests supplement previous measurements to utilize the effects over time. Pavements consisting of both asphalt and concrete have been analyzed. Furthermore, two Swedish test sections have been included in the analysis. Both elastic and viscoelastic analysis has been carried out. The project has had close cooperation and knowledge exchange with Norway, Poland, and the USA.