In close coordination between the parties involved and with advice from the engineers at S&P, a rehabilitation concept was developed that would on the one hand meet the requirements of the client and on the other hand limit the closure times to a minimum. The asphalt surface course in the affected area was replaced to a thickness of 4 cm and reinforced with S&P Carbophalt^® G. An asphalt concrete for special requirements (S) with polymer-modified binder was used for this purpose. The asphalt reinforcement was placed under the new wearing course on the previously prepared milled substrate. Subsequently, the surface was temporarily covered with a thick layer of 2/5-grain chippings to protect the newly paved surface course until it had completely set and hardened so the area could be reopened to traffic as quickly as possible.

In this scenario, the asphalt reinforcement performs two tasks. On the one hand, it increases the stiffness of the asphalt structure, distributing shear stresses over a larger area and anchoring them in the road body. On the other hand, it protects the new asphalt layer from reflective cracking of damage that may exist in the deeper asphalt layers.

Project tracking

The jointly developed solution using S&P Carbophalt^® G performed admirably despite the extremely challenging conditions. Even 6 years after the resurfacing, no damage or cracking was observed on the repaired section. It was not until 2020, 9 years after installation, that the first signs of wear began to appear in the form of incipient top-down cracking, but these had not yet reached an extent to call into question the serviceability of the repaired surface. Compared to the previously required annual repair cycle, this means that the service life of the asphalt pavement could be increased at least ninefold with the help of S&P Carbophalt^® G asphalt reinforcement grid.