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At the beginning, basic information on TRC is provided to give an understanding of the choice of material and the layout of the TRC layer. Prior to the presentation of the conducted investigations, the concept of the strengthening layer is described in Section 2. The results of the experimental investigations are presented later. In terms of the gain in capacity due to the additional TRC layer, not only regular flexural and but also shear tests were conducted. Strengthening is subject to the present paper. It is called SMART-DECK and offers a three-fold functionality comprising monitoring, corrosion protection and strengthening of the transverse system of concrete T-beam or hollow core bridges. The findings presented in the following were part of a project aiming at developing a thin TRC layer which is intended to be added on bridge deck slabs between the RC structure and the road surface. Thus, the ecological footprint of concrete structures might be improved. In consequence, the substructures and foundation of the strengthened bridge are exposed to less extra loading while CO 2 emissions from initial construction are spread over a longer period of use. This results in a more resource-efficient use of materials with a reduced additional dead weight and an extended service life. Innovative materials, such as UHPC or textile-reinforced concrete (TRC) enable considerable material savings through increased performance. For reinforced or prestressed concrete bridges, which represent the majority of the German bridge population, established strengthening methods are available, such as additional external prestressing, insertion of shear connectors, additional concrete in the compression zone or external application of CFRP sheets or lamella. If some of the required verifications cannot be met even after a more detailed structural analysis during bridge assessment, strengthening measures can provide pertinent solutions. The aim is to extend the planning horizon in order to postpone the construction of a new replacement bridge for at least a part of the affected bridges. In many countries, strategies have been developed for bridge assessment including monitoring, maintenance and design evaluation. In order to extend the remaining service life of the currently deficient structures, refined design concepts can provide a remedy that allows higher computational load-bearing capacities. Or else, there are computational deficits due to increased traffic or stricter verification. The age distribution of the existing bridges in combination with several normative changes and significant economic and demographic changes in many industrial countries lead to many structures showing damages. The experimental study revealed high increases in capacity for both bending and shear failure. A total of 14 large-scale tests on TRC-strengthened slab segments were tested under static and cyclic loading. While the strengthening effect of TRC for slabs under flexural loading has already been investigated several times, the presented test programme also covered increase in shear capacity, which is the other crucial failure mode to be considered in design. Due to the high tensile strength of the carbon and its resistance to corrosion, a thin layer with high strength and low additional dead load can be realised. Here, carbon fibre-reinforced polymer reinforcement together with a high-performance mortar was used within the scope of developing a strengthening layer for bridge deck slabs, called SMART-DECK. For numerous cases, applying an extra layer of textile-reinforced concrete (TRC) can be a convenient method to achieve the required resistance. If bridge assessment does not provide sufficient capacity, strengthening can be a pertinent solution to extend the bridge’s service lifetime. To address capacity deficiencies of bridges, refined structural analyses with more detailed design approaches can be applied. This is mainly due to changes in code provisions which came along with stricter design rules and increasing traffic, leading to higher loads on the structure. Many older bridges feature capacity deficiencies.
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