Novel Method for Improving Shear Capacity of Slabs with Intermediate Beams using FRP

Discontinuities in FRP retrofit laminates used to increase the in-plane shear capacity of concrete slabs (diaphragm shear) could introduce a serious interference in the anticipated load path. Discontinuity may occur where the continuity of laminates is interrupted due to the presence of other structural members. In the case of multi-span reinforced concrete slabs retrofitted from below, discontinuities in the FRP system occur where beams are intersected. A novel anchoring system was successfully developed and tested to introduce an effective means of connecting the FRP system to the substrate and creating continuity across the beams in multi-span reinforced concrete slabs. This innovative anchoring system was implemented in a seismic retrofit project to enhance the in-plane shear capacity of third floor and roof slabs in a high revenue telecommunication center. The proposed anchoring scheme ensured the continuity of the retrofit system and therefore created a viable load path for diaphragm shear forces.