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This paper presents a novel ductile carbon fiber reinforced polymer (CFRP) anchor system, which has been designed to ensure a controlled high capacity. The response of the anchor system was hypothesized tailorable by adding a ductile mechanism as a part of the anchor system. Three test batches, totaling 43 tests, provide the basis for a functionality sensitivity analysis and thus a threshold basis for tailoring the ductile mechanism response. The response of these were predicted using FE-simulation of three different ductility mechanism configurations and verified by tested. The tensile capacities of the final modified anchor reached a mean value of 2986 MPa, based on tests ranging from 2875 MPa to 3229 MPa. The ductile mechanism provided the intended response to the tensile behavior. An initial elastic regime with a tailored yielding regime initiation at 2330 MPa was reached, with a post elastic stage which enabled utilization of the full anchor capacity. An excellent consistency in the results was thus obtained with large elongations at a high tension magnitude. Consequently, the results furthermore enabled change of failure mode from brittle to ductile.

Strengthening of existing structures with Carbon Fibre Reinforced Polymers (CFRP) is a method that has been more common in the building sector during the last decades. The materials strength in relation to its weight is a huge advantage but the lack of knowledge in the building sector results that professionals uses more proven materials such as steel to strength structures. In this report five minor projects in which steel was the strengthening material has been analysed to see if CFRP could be a competitive strengthening material considering mainly practical and economical aspects. The main purpose of this report was to evaluate when CFRP is the most suitable option for strengthening of concrete structures. The results showed that CFRP was applicable in every project but the total cost were higher comparing to the steel solution in four out of five projects. The results indicate that it is difficult to motivate CFRP regarding the economical aspect in relation to minor project that were evaluated in this report. Nevertheless, the tendency is that the advantages with CFRP is more useful when there are more comprehensive projects such as advanced steel works and when it is necessary to save room volumes.

The performance of the most well-known models for the prediction of the contribution of FRP systems for the EBR shear strengthening of reinforced concrete beams is compared in this paper. The comparison was made using experimental results collected in a large database consisting of approximately 200 FRP strengthened concrete beams with various strengthening configurations and geometric dimensions. The results are not promising and a large scatter between the considered models was obtained. In addition, none of these models predict the ultimate shear capacity very accurately, which is of serious concern considering that some of the models are used in various design codes.