Präzisierung der Zustandsbewertung als Beitrag zur Verbesserung der Erhaltungsstrategie für Bundesautobahnen

In order to keep the federal highway network permanently efficient and available, it is necessary to optimize the maintenance strategies. To this end, the present thesis makes an important contribution with the definition, characterization and categorization of the combinations of substance characteristics (surface) (TP3) as well as the determination of the optimal positioning of the construction joint between the paved lanes in the roadway cross-section.
Preliminary studies within this work provided important insights into the single substance characteristics of the surface; these include the damage frequency and distribution in the federal highway network as well as the spatial damage extent of the individual TP3-characteristics.
The knowledge gained from the statistical analyses on the characteristics of the combinations of substance characteristics (surface) was used to select specific evaluation criteria for the specially developed scheme for categorizing the most probable causes of damage to the crack-based combinations. Based on this scheme, it is possible to specifically adjust the necessary maintenance measures to the repair of the existing damage in the road structure and thus to contribute to an optimization of the maintenance strategies.
The statistical analyses of the individual characteristics and their combinations indicated at an early stage a concentration of damage in positioning areas of the construction joints between paved lanes in the roadway cross-section. Thus, a further focus was placed on the analysis of damage occurrence and damage development of construction joints between paved lanes in the roadway cross-section. The construction joint in the roadway cross-section was identified and statistically proven to be a significant zone of weakness in the asphalt pavement - this area shows cumulative fatigue damage, such as an open construction joint or cracks, particularly frequently.
Based on the analyses of proven construction joints and their joint damage in the federal highway network as well as on BISAR calculations of the stress and strain curves for the load case “truck and car” on 3-lane federal highways, the optimum positioning of the construction joint between paved lanes in the roadway cross-section was determined. The findings obtained serve as a basis for decisions on the future design of construction joints between paved lanes and on improved positioning of the construction joint in the roadway cross-section for new construction and maintenance of federal highway sections. The results of this work can be used to avoid weak zones in road construction and to optimize and extend the service life of the paved asphalt layers.