8This paper aims to review and critically assess experimental research efforts on the seismic retrofit of 9 existing reinforced concrete (RC) beam-column joints with fibre-reinforced polymer (FRP) sheets of 10 the past 20 years. The review of the literature revealed several promising features of FRP 11 strengthening schemes. FRP retrofits can be used to address a number of different deficiencies in 12 non-seismically designed RC members framing into beam-column joints. A majority of studies 13 concentrate on joint shear strengthening and strengthening in the axis of principle stress is found to 14 be most effective. Other strategies include counter-acting the weak-column/strong-beam in non-15 seismically designed specimens by means of column flexural strengthening, as well as plastic hinge 16 relocation within the beams, away from the joint. Only a limited number of studies look at combining 17 several of these retrofit objectives into a more complete retrofit of the joint sub-assemblage. In most 18 studies it is observed that simple FRP wrapping is used for anchorage, which is not always effective. 19Instead, it is shown that anchorage by means of FRP anchors or mechanical anchors is required to 20 achieve adequate strengthening in most cases. Next to the detailed discussion of the literature, a 21 database of all tested specimens is compiled and analysed. An assessment of shear strengthening 22 design equations from major design guidelines is made based on the experimental results collected in 23 this database, highlighting the need for their further improvement. Moreover, analysis of the database 24 reveals a lack of tested specimens with realistic test set-ups, including scaled specimens, testing 25 without axial load, as well lack of slab and transverse beams. It is found that these parameters heavily 26 affect retrofit effectiveness and may lead to non-conservative results. Moreover, on average, the 27 effectiveness of repairing pre-damaged specimens is found to be similar to that of retrofitting 28 specimens without damage.Reinforced concrete (RC) structures built in earthquake prone areas and designed to resist gravity 31 loads only or before the introduction of modern seismic codes (pre-1970's or 80's), typically display 32 several deficiencies resulting in inadequate behaviour under seismic loading. In particular, the 33 hierarchy of strengths around beam-column joints plays a critical role in the overall cyclic behaviour of 34 RC structures. Avoiding premature failure of said joints is hence a fundamental principle in modern 35 seismic design to allow the framing members reach full capacity (Kappos and Penelis 1996). 36Adequate energy dissipation under seismic loading also relies on an appropriate hierarchy of 37 strengths between the framing members of the joints. To achieve larger global structural 38 displacements and hence higher ductility under seismic loading, modern seismic design guidelines 39 aim to ensure beam-hinging precedes column-hinging mechanisms (Fardis 2009). 40For existing structures...

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