Paving blocks in lab tests
| Titel | Title Erstellung eines Verfahrens zur rechnerischen Dimensionierung und zur Prognose des Verhaltens von Pflasterbefestigungen für konzentriert eingetragene schwere Verkehrsbelastungen mit häufiger Frequentierung | Development of a method for the mathematical dimensioning and prediction of the behavior of pavements for frequent concentrated heavy traffic loads Förderer | Funding Bundesanstalt für Straßenwesen (BASt) |
Report 2023
Deformation of paving block structures
Test set-up with rectangular blocks – traverse and inductive displacement transducers
The design of paving block structures is currently carried out in Germany on the basis of empirical findings in accordance with the Richtlinien für die Standardisierung des Oberbaus von Verkehrsflächen (Guidelines for the standardization of the superstructure of traffic areas, RStO) 12. Despite the fact that the construction method conforms to the regulations, damage in the form of rutting or longitudinal unevenness sometimes occurs during the warranty period, but often within the planned service life of the paving. As a result of previous research work, it seems possible to design more durable pavements than before by applying a numerical design of block pavements, taking into account the deformation behavior of the unbound base layers in a realistic manner.
The Federal Highway Research Institute (Bundesanstalt für Straßenwesen, BASt) awarded the Society for Knowledge and Technology Transfer (GWT-TUD GmbH) the contract for the R&D project “Development of a method for the mathematical dimensioning and prediction of the behavior of pavements for frequent concentrated heavy traffic loads”.
The working program of the research project included the investigation of the deformation behavior of unbound construction material mixtures (base course materials) using triaxial tests. Based on these test results, the mechanical behavior of the base course materials was modeled. The dimensioning method presented as a result of the research work is based, among other things, on the calculation of different stress states using the finite element method. Large-scale tests were carried out in the Otto Mohr Laboratory at TU Dresden to calibrate and verify the dimensioning procedure. Two test areas with different concrete paving stones were prepared for this purpose. A suitable material was selected for the base course from the construction material mixtures previously analyzed in the triaxial testing device. The applied vertical load corresponded to 1 million passages with high axle loads. This was applied synchronously and cyclically with a hydraulically controlled cylinder (load stamp) via two load distribution plates.