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An experimental study of geosynthetics was carried out on a shaking table to investigate the relationship between dynamic friction resistances and shear displacement rate and to examine other frictional characteristics of geosynthetic interfaces. A cyclic, displacement rate-controlled experimental setup was developed. The subsequent multiple rate tests showed that interfaces that involve geotextiles have unique shearing characteristics that can be differentiated from the interfaces not involving geotextiles. It was found that shear strengths of geosynthetic interfaces tend to increase with increasing displacement rate for combinations of geosynthetics that involve geotextiles; whereas, shear strengths of interfaces not involving geotextiles do not.

The 1H- and 13C-NMR-parameters indicate a delocalization of the negative partial charge at the phosphorus in the lithiumorganophosphides. The equilibrium between solvated monomeric ion pairs and solvated dimers is sensitive to the solvent. At 175 K in solution of diethylether dimers dominate. The dimerization is hindered in phosphides with bulky substituents. The intermolecular exchange of lithium, observed in the NMR-spectrum goes through a dimerization.Für Lithiumorganophosphide zeigen 1H- und 13C-NMR-Parameter eine Delokalisierung der negativen Partialladung am Phosphor. Die Lage des Gleichgewichtes zwischen solvatisierten monomeren Ionenpaaren und solvatisierten Dimeren ist empfindlich vom Lösungsmittel abhängig. Bei 175 K dominiert in Diethylether die dimere Form. In Phosphiden mit voluminösen Substituenten ist die Dimerisation behindert. Der im NMR-Spektrum beobachtete intermolekulare Lithiumaustausch erfolgt in THF-Lösung über eine Dimerisierung.

A new method is presented for the analysis of a bolted flange subjected to bending moments. Bolt axial cyclic loads are calculated using the force ratio method. Bolt bending moments are found with the new analysis scheme presented. A key factor in the analysis is the area in compression of the flange. Experimental results are used to substantiate the theoretical methods. A finite element analysis was also conducted to support the theory.

Hybrid parts are strongly moving into the focus for lightweight applications. Unfortunately, the accurate, simulative design, which comprises the accurate prediction of final part geometry, is still a challenging task. In the scope of this paper, an approach to improve the accuracy of appropriate finite element simulations is presented. To this end, the manufacturing history of the hybrid part is considered within the simulation of the part behavior. To create a finite element model of the considered hybrid composite, the intrinsic manufacturing process is modelled first. This includes the modelling of the thermoforming process of a fiber reinforced polymer as well as the sheet metal forming process for the fabrication of form fit elements. Then, the geometry of the hybrid part is deduced from the geometries of the single components. Afterwards, the material properties, including the local fiber volume content as well as the local fiber orientation, are mapped to the finite elements. Consequently, a workflow to create a finite element model which considers manufacturing history is developed and successfully tested.

Hybrid parts, which combine low weight with high strength, are moving into the focus of the automotive industry, due to their high potential for usage in the field of crash-relevant structures. In this contribution, the development of an intrinsic hybrid composite is presented, with a focus on the manufacturing process, complex simulations of the material behaviour and material testing. The hybrid composite is made up of a continuous fibre- reinforced plastic (FRP), in which a metallic insert is integrated. The mechanical behaviour of the individual components is characterised. For material modelling, an approach is pointed out that enables modelling at large strains by directly connected rheological elements. The connection between the FRP and the metallic insert is realised by a combination of form fit and adhesive bonds. On the one hand, adhesive bonds are generated within a sol gel process. On the other hand, local form elements of the metallic insert are pressed into the FRP. We show how these form elements are generated during the macroscopic forming process. In addition, the applied sol gel process is explained. Finally, we consider design concepts for a specimen type for high strain testing of the resulting interfaces.