Prevention of reflection cracking - Landesstraße 3144 - Lauterbach, Germany
The state road 3144 connects the districts of Sickendorf and Wallenrod of the district town of Lauterbach in the Vogelsberg district of Hesse. Due to the advanced age of the asphalt pavement and the presence of cracks in many areas, a 5-kilometre stretch of the road was repaired and reinforced with S&P asphalt reinforcement by Hessen Mobil, Schotten, in the summer of 2022.
On this page
- Topic
- Prevention of reflection cracking
- Object
- Landesstraße 3144
- City
- Lauterbach
- State
- Hesse
- Country
- Germany
- Date
System
Project Description
Situation
In order to make optimum use of the existing substance of the road body and to increase the structural value of the pavement, Hessen Mobil planned to carry out the rehabilitation in high paving. If there are pronounced damage patterns in the existing asphalt pavement in the form of individual cracks, transverse cracks and mosaic cracks, there is a risk of cracks reflecting into new asphalt layers. This is often followed by further damage due to water penetration. This in turn leads to a loss in infrastructure value and the road investment is quickly wiped out.
Solution
In order to achieve sustainable rehabilitation success and to protect the infrastructure capital, Hessen Mobil Straßen- und Verkehrsmanagement, Schotten decided to use a S&P asphalt reinforcement between the new asphalt layers. The existing pavement was milled off by approx. 1 - 2 cm and rehabilitated with a base course AC22 T N and a surface course AC8 D N using the high paving method. The pre-bituminised asphalt reinforcement S&P Glasphalt® G was used on the new base course.
The laying of the asphalt reinforcement was carried out by S&P certified installers Straßenbaustoffe Stuttgart Vertriebs GmbH in close coordination with the construction company Bickhardt Bau AG. In this way, the reinforcement could be optimally integrated into the construction sequence. With the help of the S&P installation machine, the 1.95 m wide S&P reinforcement grids could be laid quickly and without wrinkles. The wearing course could then be laid without any problems.
Function of the asphalt reinforcement
The asphalt reinforcement S&P Glasphalt® G consists of glass fibre strands that are 100 % impregnated with bitumen. The mesh has no fixed knots, which makes it possible to lay it in curves and to adapt the mesh to the subgrade or the grain structure. The largest grain of the surface course can form an interlocking connection with the underlying layer through the grid meshes and achieve a very high layer bond. This ensures that the fibres of the asphalt reinforcement are optimally bonded and can effectively absorb and anchor crack-generating tensile forces.
This effectively prevents the reflection of cracks from the existing pavement into new asphalt layers and the resulting consequential damage. The reinforcement also increases the overall stiffness of the system and thus prevents future stress cracks.