Influence of multiple anchor arrangement in the behaviour of FRP-to-concrete anchored joints

摘要

The effectiveness of fibre-reinforced polymers (FRP) external reinforcements is limited by premature delamination from concrete. In recent years, various anchoring systems were developed for FRP sheets. Among these, FRP anchors stand out for their effectiveness. When the unit strength of a connector is insufficient, multiple anchors may be employed. This paper presents an experimental campaign consisting of single shear tests on CFRP anchored narrow (100 mm width) and wide (200 mm width) sheets in concrete substrates. One anchor was installed in narrow sheets for comparison with wide sheets. Wide sheets were tested with one anchor and with two anchors transversally distributed to evaluate the influence of multiple anchors. Results from both literature and tests show that an optimal arrangement of one anchor in narrow FRP sheets or two transversally distributed anchors in wide sheets can be equivalent, which allows the anchored joints to develop more than twice the bond strength.