Structural Concrete 02/16

Taken from the technical paper Background to the European seismic design provisions for retrofitting RC elements using FRP materials: 

"[...] Fibre reinforced polymers (FRP) were introduced into civil engineering practice in the early 1990s, but they only became popular after they became known for their effectiveness as a fast remedy when retrofitting damaged reinforced concrete and masonry structures in the wake of the catastrophic earthquakes at the end of that decade (Northridge, 1994, Kocaeli, 1999, Athens, 1999). Since that time, extensive research has been undertaken to support design procedures for retrofits with FRP wraps and laminates, leading to several versions of design guidelines. [...] A large part of the research effort was directed towards the development of confinement models, whereas all other actions were primarily considered for static loads (shear and anchorage). Earthquake retrofit detailing was hampered by the need to address global structural response issues as well in order to determine the retrofit priorities, whereas the literature on models that could support the development of guidelines was already marked by significant discord regarding the deformation indices of retrofitted behaviour, thus complicating the detailing process.

The aim of this paper is to establish a new-generation framework for the design of seismic retrofits using FRP materials. Following prevailing earthquake and design practice, the paper establishes performance-based criteria for global and local retrofit requirements so that the rehabilitated structure can develop acceptable, repairable levels of damage in a severe earthquake and minimal (limited) levels of damage in the frequent event. The aims of FRP retrofit designs are the enhancement of strength and deformation capacity as well as the mode of failure control of the structure and its individual structural members. It is intended that this paper should serve as the background for the development of European seismic retrofit provisions using FRPs. [...]"

The full article is available online for free until November 19th, 2016. Contiune reading on WileyOnlineLibrary. 

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