With over 5000 km of national highways in the Netherlands, the Dutch Ministry of Infrastructure and Water Management (Rijkswaterstaat; RWS) is spending approximately 200 million euro a year on maintenance of asphalt pavements. To decrease these costs, and thereby decrease the amount of tax money needed, RWS is starting to use big data techniques to predict “just in time” maintenance.
Beeldbank
RWS uses predictions of the asphalt lifetime to estimate when and where road maintenance will be needed. The current practice of programming road maintenance is based on a course prediction, in combination with many operational parameters. This has resulted in maintenance frequently being done either too early (before the materials are fully used) or too late, as an emergency repair of damaged roads, which can lead to extra costs and environmental and traffic burden.
The main failure mechanism of asphalt on Dutch highways is raveling. Raveling data is collected with a Laser Crack Measurement System. In current practice, the data of a road segment of 100 metres is typically summarised in nine parameters. The prediction of asphalt lifetime based on these parameters in consecutive years is correct one third of the time. Using the available data in a more detailed manner, e.g. considering data of shorter road segments and combining and analysing the measured data before it has been summarised, the prediction consistency in consecutive years has doubled to two third of the time. This is a major improvement!
The effect of using shorter road segments can be illustrated as follows: Based on the available data, a segment of asphalt currently gets a quality score between 1 and 5. However, there can be large differences in quality within a segment of 100m. Trees, for example, decrease the quality of the road underneath. Meanwhile transitions between types of asphalt, for instance coinciding with a bridge location or with the end of a batch of asphalt production, also have an influence. In a span of 100m, you can then have three different asphalt quality levels, scoring together an average of 3 (meaning no maintenance is needed), while in reality there will be parts scoring a 1 and parts scoring a 5. This can be overcome using shorter road segments.
To be able to have a clear overview of all this data, RWS has developed a dashboard which visualises the quality of all asphalt of the national highways in the Netherlands. The creation of this dashboard is part of the European project BE-GOOD which stimulates the use of open data.
Improving the accuracy of asphalt lifetime prediction enables better maintenance planning. The planning is based on more aspects than asphalt quality alone, such as minimizing traffic hindrance, combining asphalt maintenance with other road maintenance, budget planning, contract details, and guarantee issues. At present, these other aspects sometimes dominate the maintenance planning, because the prediction of residual asphalt lifetime is of insufficient quality. With big data analysis a turnaround appears to be feasible.
As a result, premature maintenance may be significantly decreased, thus saving on costs and on environmental impact due to CO2 emissions and (raw) material usage. Furthermore, timely maintenance avoids ad-hoc and unforeseen maintenance which often lead to traffic congestion. And a very important advantage is the increased road safety for all road users due to optimised asphalt conditions.
For more information about this project, watch the video below:
The capitalisation: expansion to new geographical areas
The capitalisation of the original solution started already in January 2020, before the ending of the original BE-GOOD project. The Province of Gelderland joined a presentation of our solution. During this first meeting ‘the spark must have flown’ of what is now a very much appreciated cooperation of two road maintenance governments within the Netherlands.
Because we have so much in common regarding our methods of maintaining our asphalt roads, we decided to cooperate based on the solution that RWS had developed. Although there is a difference in the geographical areas that we cover (see image), we have much more in common: asphalt types of roads, road intervals (100 m.), legal maintenance necessities, safety, traffic flow etc.
These similarities showed themselves profoundly during the cooperation. After the first meeting we agreed on elaborating the eventual “Joint asphalt dashboard”, which production was financed by RWS and supported by BE-GOOD.
A quote request for SME’s was published and we received an offer which has resulted in an asphalt dashboard for both parties. The main features of this dashboard are four sub screens with connected maps, graphs and pictures and an import & export ‘button’ for datasets.
The lessons learned during this whole process of procurement, development and evaluation of the new dashboard are:
- Think ahead, i.e. make up very clear (pre)conditions and requirements for your end product. In which we focused on using so-called standard building blocks (software), which make it easier to maintain software products.
- We now have two separate dashboards although all features are exactly the same. This is caused by the usage of different data filters in relation to the different datasets and the fact that there are different user groups because of software license matters.
Want to know more?
Partner: Ministry of Infrastructure and Water Management
Contact: Pieter Lips
pieter.lips@rws.nl