The capacity of GFRP anchors in concrete and masonry structures

Fiber-reinforced polymer composites, due to their exceptional lightweight and strength characteristics, are now widely used to strengthen reinforced concrete or masonry structures. Among many applications, they are used as anchorage systems using preformed pultruded bars or high-strength fiber ropes to be impregnated in situ. In both cases, the anchoring part is a bar-type dowel component inserted into holes filled with a binder or adhesive material. One of the lesser-studied issues of their use is the pull-out strength of the anchorage system. It depends on several factors, such as the type of substrate, the anchorage bar diameter, the bonding agent, the anchorage length, etc. This paper summarizes the anchorage mechanism of GFRP bars through the analysis of several experimental data. The shortcomings of the current state of knowledge and some useful recommendations for further studies are presented. Thus, the paper is aimed at contributing to a better evaluation of the effectiveness of anchorages in FRP strengthening systems, and in particular of the GFRP bars used for anchoring fiber meshes and fabrics to prevent the overturning of infill walls in reinforced concrete buildings or walls in masonry buildings.