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In general, today two types of launching bearings are used in the construction of large steel and steel concrete composite bridges: sliding rockers and systems with hydraulic bearings. During incremental launching, the centre of the webs of the superstructure is not perfectly in line with the centre of the launching bearings due to unavoidable tolerances. These eccentricities are not considered in the current design against plate buckling according to DIN EN 1993-1-5 [2]. Furthermore, there is a significant difference between the different types of launching bearings due to the boundary conditions. At the Technical University Munich, large-scale buckling tests were carried out on longitudinally stiffened plates under biaxial stresses with different types of launching bearings and eccentric load introduction. The test results as well as the results from the validated numerical model demonstrate the influence of different types of launching bearings on the buckling behaviour. The results are compared with the buckling verification according to the reduced stress method proposed in DIN EN 1993-1-5 [2].

In general, today two types of launching bearings are used in the construction of large steel and steel concrete composite bridges, sliding rockers and systems with hydraulic bearings. During incremental launching, the center of the webs of the superstructure is not perfectly in line with the center of the launching bearings due to unavoidable tolerances. The advantages and disadvantages of the respective systems are under discussion. At the Technical University Munich, large-scale buckling tests were carried out on longitudinally stiffened plates under biaxial stresses with different types of launching bearings and eccentric load introduction. In this paper the test results as well as differences of the respective systems are presented. Based on experimental results, a numerical model is validated. The test results as well as the results from the validated numerical model demonstrate the influence on the buckling behaviour from different types of launching bearings.

Floodplains provide a variety of hydrological and ecological functions and are therefore of great importance. The flooding frequency, as well as the height and duration of inundations are particularly relevant for ecosystem states and are dependent on the exchange between surface water and groundwater. In this study, we developed a fully distributed model approach to simulate distributed groundwater levels in a floodplain in Hesse, Germany (14.8 km2). To overcome the problem of large computation times we simplified the surface water equation. Thus, the water surface of flooding is at the same level everywhere and the dynamic effect of the flooding is ignored. In this way, it was possible to run the model 5,000 times and investigate its parameter uncertainty using Latin hypercube sampling. Behavioral model runs were selected based on a threshold criterion of a mean root mean square error that was smaller than 0.26 m. All the simulated groundwater wells show an individual RMSE between 0.17 and 0.41 m for the calibration period. Regarding the parameterization, the model shows rather large variance in parameters that are capable of generating good simulations: a range of saturated conductivity of 2,793 m/day, porosity of 0.4 m3/m3, residual wetness of soil of 0.2 m3/m3/soil and range of soil thickness of 2.9 m.