Residual salt models for decision support systems

Purpose and goal

Forecast-controlled dynamic road maintenance has proven to lead to increased productivity as road condition forecasts has been integrated with route optimisation in previous sub-projects. Further developing and verifying with respect to the amount of residual salt on the road would further increase cost efficiency. It is crucial to be able to describe the salt and water balance on the road surface. The goal was to improve existing residual salt models, which almost succeeded, but it needs more validation to be able to know for sure that they are correct.

Expected results and effects

The project started by completing a literature review to see what calculation models are available to calculate residual salt. After field measurements, the measured salinity levels on the road have been compared with calculated values based on road conditions and current weather conditions. Of the results that have been produced, has the fit been better than expected. The differences between measured and calculated values were smaller than we had expected. However, more validation measurements of residual salt are needed to be able to rely on the model calculations.

Planned approach and implementation

The aim of the project was to measure the residual salt of the road and then analyse the results of the field measurements together with existing models´ calculations of the amount of residual salt of the road in question. The model can then be adjusted to get as close to reality as possible and new validation measurements can be performed. However, winter weather was not as planned, and all the field measurements could not be carried out. The project will therefore continue this coming winter.