Road Construction Technology - Test Engineering

  Graphic: City view with construction vehicles Copyright: © ISAC

The research group for Test Engineering in the field of Road Construction Technology is divided into three closely related areas of work: testing technology, construction process/installation technology, and surface properties.


Research Focus in Traffic Construction Technology - Test Engineering

Laboratory Testing

The research focus of the testing technology is in the areas of asphalt and concrete technology. Research focuses on the development of test methods for performance-based bitumen and asphalt testing and the optimization of the service properties of bitumen and asphalt. The development process is carried out on a macroscopic as well as molecular level. In addition, interdisciplinary cooperation is used to investigate and optimize hydraulically bound construction materials.

Multifunctional road construction materials also fall within the scope of test engineering: the development of water-permeable pavement structures made of alternative construction materials, the market placement of novel road construction materials based on polyurethane, or the expansion of the function of traffic surfaces. In view of increasing demands on traffic infrastructures and changing climatic conditions, it is essential to adapt construction materials accordingly.

The institute's own materials testing laboratory is capable of fully comprehensive analysis of the construction materials bitumen and asphalt. When testing asphalts, the focus is on deformation, fatigue and low-temperature properties as well as compaction behavior. In the case of concrete structures (e.g. continuously reinforced concrete pavements), the life cycle is analyzed comprehensively.

Installation Technology

The Construction Process / Paving Technology work area deals with the paving process and the quality criteria of road pavements. Among other things, the optimization of asphalt paving and compaction processes as well as the optimization of asphalt pavements including the paving and compaction process are of interest. The same applies to the development of methods for non-destructive bearing capacity measurement and evaluation of the pavement.

To optimize paving processes, ISAC is pushing the digitalization, automation and optimization of construction processes. A frequent source of error is the interaction between man, machine and material, and improving this has a lasting impact on the quality of the road structure. In addition, digitized paving processes are much more reliable, errors are detected at an early stage and can be eliminated using suitable automated control algorithms. In this way, time-consuming and cost-intensive reworking, or even complete rebuilding of the asphalt surface if necessary, can be avoided.


The surface of a roadway is in constant interaction with the various road users, be they motorized vehicles, bicycles or pedestrians. All users have individual requirements for the roadway. These requirements overlap in places, but can also vary widely.

The evenness of road surfaces is of key importance for a number of reasons. An uneven road has a negative effect on ride comfort in the vehicle and can be detrimental to the back in the long term; it also puts stress on the axle and body of the vehicle and has an impact on the load/cargo. Uneven surfaces also stress the road, e.g. additional dynamic axle loads occur in the case of sinking.

The non-contact measurement of the skid resistance of a road surface is the focus of development, as is the development of a sensitive, functional surface layer. The development of water-permeable surface course systems with the aim of decentralized drainage and simultaneous reduction of the heat island effect are linked to the climate change that has already occurred. The emission of microplastics has to be included in the sustainability considerations of modern road construction. Corresponding test methods have been developed and tested at the Institute of Highway Engineering.