FRP grouted anchors contribution to the masonry walls OOP response through the kinematic approach of limit analysis

Grouted anchors made of fiber-reinforced polymer (FRP) pultruded bars are recently used to improve the masonry walls out-of-plane (OOP) response. However, despite the availability of some experimental investigations on different typologies of anchors embedded in different types of masonry, assessing their contribution to the OOP response of masonry walls is still an open issue. To this aim, a modeling approach already proposed by the authors in the framework of limit analysis is improved in this paper by addressing two issues: i) a better definition of the geometry of the possible failure mechanisms in the strengthened condition, and ii) a simplified formulation for calculating the contribution of the anchors to the stabilizing moment, which allows comparing several design solutions easily. First, such a simplified formulation is verified against the non-linear kinematic approach validated in previous works; then, it is applied to investigate different design solutions, which account for some significant parameters affecting the behavior of both the anchors and the masonry.