Geothermal Tempering of Bridge Surfaces

Project Participants:

Prof. Dr. R. Bracke
Prof. Dr. M. Mertens
Prof. Dr. A. Henk
Dipl.-Ing. (FH) T. Eicker
J. Schiller


„F&E Schwerpunkt Geothermie“ of the Ministry form Innovation, Science, Research and Tehcnology of North Rhine-Westphalia

This study analyses the geological and the construction physical boundary conditions for the geothermal tempering of the surfaces of bridges.

In summer periods the temperature of roadbeds easily reaches temperatures of up to 60°C (140°F) due to its solar heat gain. This enormous warming combined with the increasing number of heavy load vehicles supports the formation of damages, such as lane grooves.

In winter periods the danger of unexpected and rapid black ice formation exists especially on bridges. Due to its exposed situation a bridge cools faster as the adjacent conventional road beds.

These processes on the one hand cause interference with and dangers for the traffic and on the other hand damages of the asphalt surface and the body of the bridge itself. By heating or cooling the relevant construction elements of bridges these negative influences can be counteracted.

Within the scope of this study the potential of a geothermal tempering of bridge constructions is analysed, exemplified by the “Klosterbrücke” in Hattingen. The concept this study is based on envisions geothermal bridge cooling in summer periods and geothermal heating in winter periods with the heat stored in the ground from summer months.

The study comprises two parts:

In the first part geo and petro physical properties of the soil in the project area are determined with the help of core drillings. Based on this analysis various systems, including a heat pipe arrangement, are evaluated and modelled.

In the focus of the second part of this study there are the logging of climatical conditions in the range of the “Klosterbrücke”, the simulation of the temperature effects on the bridge, physical analysis of asphalt core drillings and finally the design of the pipe work system (displacement, flow temperature and velocity).


Zusätzliche Information

geological survey map of the area "Kosterbrücke" (source: GD NRW)

Planning Data:
length    865 m
width    13,5 m
height    3,00 m
asphalt    7500 m²
evel.      88 m a. sl

functional concept for the surface tempering (source: FTD)