Road rehabilitation of of district road

Project description

Rosenstrasse in Ochtrup leads directly to the Dutch/German border and therefore carried an extremely high volume of heavy goods vehicles until the completion of a new bypass in 2005. But even today plenty of local drivers still like to take the shorter route along Rosenstrasse. In 1996 Rosenstrasse was reinstated over its full carriageway width to rectify substantial damage due to alligator cracking. The initial design called for the existing 5 cm thick asphalt surface course to be milled off and replaced. After milling off the surface course, it was apparent that the binder course and even the base were also severely cracked and in very poor condition. An alternative design was required. For reasons of finance and time constraints, it was decided to install HaTelit asphalt reinforcement directly on the milled substrate. This measure was intended to prevent early penetration of the existing cracks through the new surface course and therefore extend the period to the next reinstatement. During the works HaTelit was laid in accordance with the installation guidelines and then covered with 5 cm asphalt concrete 0/11 surface course.

Solution

For reasons of finance and time constraints, it was decided to install the asphalt reinforcement directly on the milled substrate. This measure was intended to prevent early penetration of the existing cracks through the new surface course and therefore extend the period to the next reinstatement. During the works the geogrid was laid in accordance with the installation guidelines and then covered with 5 cm asphalt concrete 0/11 surface course.

Project follow-up

2002, 2009:
A visual inspection of the condition of Rosenstrasse was carried out in 2002 and 2009. At these times, no cracks have been appeared in the asphalt concrete surface and the responsible authority were able to confirm that the use of HaTelit has proved to be successful in practice.

August / September 2009:
TÜV Rheinland LGA Bautechnik GmbH, Weimar Office has inspected and assessed the condition of the carriageway along the length of Rosenstrasse reinstated in 1996 with
respect to crack formation. The visual inspection of the carriageway surface found it to be almost free of damage.

A small amount of transverse cracking was present at one location on the outer edge of the carriageway reinforcement. Small longitudinal cracks were evident at a few other spots which were also on the outer edge. Records of the installation show that no reinforcement is present in the outer edge areas. TÜV Rheinland confirms: „The whole of the rest of the carriageway is free of cracks.“

March 2013:
In context of a master thesis, a visual assessment was carried out to verify the pavement condition of the Rosenstrasse in 2013 (Quiel, 2013). Few cracks in the border area of the road and at some manholes and gullies have been observed, which do not indicate any connection with the asphalt reinforcement layer. To further investigate the pavement situation, a core sample has been drilled to test the interlayer bond according to Leutner. Between the asphalt bearing course - polyester reinforcement - and the upper asphalt layer a maximum shear force of 24 kN was measured. After evaluating the whole data record of the “Rosenstraße” it was found, that the condition, after a lifetime of 17 years, was still very good.

Conclusion

The road has remained in perfect condition and further reinstatement has not been necessary. The use of the asphalt reinforcement grid has proved itself a success as a method of reinstatement in every respect.