Measurement data based load analysis of precast concrete pavements of motorways

摘要

In Austria, about 40 % and in Germany about 30 % of the motorway and expressway network are concrete pavements. However, very little is known about the stress conditions and temperature loads actually acting in concrete pavements. There is little in-situ data available, mainly because of the difficulties involved in measuring these conditions in a real paving environment. In the course of a research project, precast slabs were used for the first time to repair concrete pavements in a highway in Austria, and these were also extensively equipped with embedded fiber optic sensors. In an in-depth analysis of the measurement data of a period of two years, temperature changes, extremes as well as gradients in connection with external weather conditions are evaluated. With regard to the formation of cracks and constraints in the slab, on the one hand measured strains without traffic load are analyzed, on the other hand a statistical analysis of the measured impacting traffic load changes is carried out. In the second section, based on a calibrated nonlinear FE model, a combined analysis of the unsteady stress profile of the slab under dynamic traffic loading with varying temperature-mechanical loading is performed. After comparison with measured data, the dynamic stress maxima acting in the plate can be determined.