By using non-metallic textile reinforcements for concrete structures, the concrete cover can be reduced significantly compared to ordinary steel-reinforcements resulting in thin-walled, slender and light-weight concrete structures. The weight of the structure can be largely reduced which is important especially for prefabricated concrete members. Next to non-impregnated textiles, today, textiles which are impregnated are mainly used as reinforcement. Due to the impregnation and the following curing process, tensile stresses up to 3000 MPa can be achieved depending on the fiber material. Furthermore, impregnated textiles can be shaped both as planar and spatial reinforcement structures, additionally, are robust and inherently stable and, thus, are suitable as reinforcements in concrete structures. Today, fibers made of alkali-resistant glass or carbon are commonly used as reinforcing materials combined with epoxy-resin or styrene-butadiene as impregnation-materials. For the design of textile-reinforced concrete structures it is necessary to use calculation models, which have been applicable only for non-impregnated textiles. This PhD-Thesis deals with impregnated textile reinforcements for concrete members. Experimental and theoretical investigations regarding the load-bearing behavior under tensile loads, bending moments and shear forces are presented. Furthermore, the bond behavior is characterized and, with the help of the derived bond laws, anchorage lengths as wells as overlapping lengths are derived. Those lengths are in the range between 20 mm to 100 mm for textiles which are impregnated with epoxy resin and between 120 mm to 320 mm for styrene butadiene. In addition it is shown, that the bond laws are suitable for calculating crack widths. The theoretical investigations are based on an experimental database, which has been build up within the scope of this thesis and consist of nearly 600 single tests. The tensile behavior is influenced by the lateral contraction of the rovings. For bend-ing loads it is shown, that the resistant bending moment can be calculated in a pure mechanical way similar to the procedure as it is known from steel-reinforced concrete members. The shear-behavior has been investigated on slabs (rectangular cross-section with slab thicknesses between 30 mm and 60 mm, without shear reinforcement) and I-beams (with and without shear reinforcement). The main failure mode of the slabs was a diagonal shear-failure occurring already at small reinforcement-ratios. Next to the transfer of the shear loads over the compression zone a distinctive dowel-action was investigated, which can be up to 50% of the overall shear force. In contrast to this, the main shear forces of the I-beams without shear reinforcement were transferred via the compression zone. For the beams with shear reinforcement it was found, that the shear reinforcement can be utilized up to 40% of the strain observed in the roving tests. Finally, engineering models for tensile loads, bending moments and shear forces have been derived, which can be used now for calculating concrete members reinforced with impregnated textiles.
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