Fredrik Hellman


Picture of Fredrik Hellman

Research results from Fredrik


Differences in the road structure laterally

For many years, reconstruction of roads has been built on the sampling of existing materials in the road structure. There are various methods to accomplish this, which means more or less damages in the road. From experience, we know that it may...

Energy ashes for construction purposes

Today in Sweden, biofuels and waste are the main fuels for the production of district heating and contributes to production of electricity. During combustion of biofuels and waste, it is also generates residues, so-called energy ashes. Large parts...

Comparison of the mechanical properties and degradation of wheel load

To study the correlation between the degradation of unbound base layer and mechanical properties (primarily Los Angeles test but also micro Deval test) a number of materials has been exposed by wheel load of VTI’s Heavy Vehicle Simulator (HVS). The...

Recycling reclaimed road material in hydraulically bound layers

The European Direct-mat project provided a significant contribution to increasing recycling reclaimed road wastes. Part of the project was dedicated to the recycling of various reclaimed road materials in new hydraulically bound layers. This paper...

Energy production from roads and road environments

The report aims to identify new technologies for energy harvesting and the ability to use them in the road and the surrounding road area. The survey focuses on the materials and methods that may be used in the Swedish (cold) climate. The report can...

Evaluation of deep-drainage and infiltration in road verge along road 126, Torpsbruk

This report contains additional data from the study of moisture, drainage and groundwater along highway 126 near Torpsbruk, Sweden. The following are the main conclusions to be drawn from the experiments with sealed road verge and deep drainage...

Investigation of mechanical deterioration of unbound materials due to heavy traffic...

In Sweden the rock qualities are based on mechanical analyses such as the Studded Tyre Test, Microdeval and Los Angeles Tests. One of the issues in this project is whether these tests are sufficient to determine the rock quality. The Heavy Vehicle...

Mica in rock material for road construction

Mica is a common mineral in the Swedish bedrock and in some places the levels are high. Two important factors when it comes to road damages caused by high amounts of mica have been identified: moisture and frost damage. The Swedish Transport...

Recycling of road materials into new unbound road layers

Most European countries are active in the field of recycling road materials, but knowledge and practice differ between countries. The European project DIsmantling and RECycling Techniques for road MATerials – Sharing knowledge and practices aims at...

Climate change adaptation of road construction, operation and maintenance

The global climate change is a reality and affecting society and transport systems. Climate change adaptation of transport systems will make the means of transportation more resilient and decrease the risk and magnitude of disruptions. Generally,...

Evaluation of deep drainage and the effect of sealed road verge and embankment slope...

Experiments show that the deep drainage system is an effective method to control the groundwater table and, concerning road construction, it is recommended as a method when the road is located in earth cut below the ground surface in combination...

Residual life estimations of pavements

This report deals with a concept applying residual value estimations to applications in optimisation and procurement of road construction and maintenance. The purpose is to develop a framework and concept for tieing together technical and economical...

Quantitative petrographic analysis of rock material

The main mineralogical properties of rock materials used in road construction are described from a technical perspective in this VTI report. It is the quality of the rock material in combination with pavement design that determines future...

Control and follow-up of fly ash roads

Stabilization of unbound layers of road structures is a promising technique from technical, economical and environmental point of view. The need of demonstration projects on road sections to show the relationship of laboratory measurements and field...