Analytical and numerical modeling of composite-to-brick bond

Abstract

In masonry components strengthened with externally bonded composites, good bonding is one of the most important aspects governing structural behavior, since failure usually takes place with detachment between reinforcement and substrate. This type of event is a brittle, sudden and therefore undesirable failure mechanism; nor does it allow the full strength of the reinforcement to be exploited. Many experimental data on bonding have recently become available from a Round Robin Test carried out within the framework of RILEM TC-223. In the present paper, experimental tests were simulated at increasing levels of complexity; bond behavior was first studied with an analytical model based on bi-linear representation of bond law. Two-dimensional and three-dimensional finite element analyses were then performed, according to various bond-slip laws. In particular, a number of bi-linear and non-linear interface laws were used, calibrated according to several strategies but with the same experimental population. Lastly, several commercial codes and types of finite elements were examined. This work may be said to represent a numerical Round Robin Test, with various simulations and modeling approaches. Analytical and numerical results are compared with experimental ones, in terms of both overall behavior (load to displacement curve) and local behavior (strain profiles on reinforcements at increasing load values), showing the importance of both types of information in order to obtain reliable predictions of experimental results

Experimental bond tests on masonry panels strengthened by FRP

“…Detailed knowledge of the interface behaviour allows to perform an accurate numerical analysis, where between the FRP reinforcement and the masonry substrate can be placed a cluster of zeroethickness interface elements [40,41] characterized by the analytical laws calibrated as described.…”

The Bond-Slip Relationship at FRP-to-Brick Interfaces under Dynamic Loading

“…Numerous experimental studies of FRP–substrate interfaces have shown that the FRP stiffness and the substrate strength are the main parameters affecting the bond–slip relationship [ 20 , 29 , 34 , 38 , 41 , 54 ]. In this section, firstly, the effects of single variables of FRP stiffness and brick strength on the bond–slip relationship at the FRP-to-brick interface were investigated.…”

On modelling brick/mortar interface via a St. Venant-Kirchhoff orthotropic soft interface. Part I: theory

“…The model proposed in this paper is expected to be useful in all those mechanical problems where solid interfaces together with geometrical and material nonlinearities have to be taken into account in a simple and reliable way at the macroscale. Potential applications could range from the bonding characterisation of cold-welded metallic joints (Zhang and Bay, 1997;Lu et al, 2010) to the collapse of FRP adhesive joints (Ascione, 2009b,a) and the simulation of masonry-FRP bond (Basilio et al, 2014;Ceroni et al, 2014), with special attention to the modelling of GFRP beams obtained by bonding simple panels (Ascione et al, 2015). In particular, its applicability in modelling brick/mortar interfaces is illustrated in Section 4.…”