Interfacial stress analysis and prediction of debonding for a thin plate bonded to a curved substrate

Abstract

This paper focuses on the analytical and numerical modeling of the interface between a rigid substrate with simple constant curvature and a thin bonded plate. The interfacial behavior is modeled by independent cohesive laws in the normal and tangential directions, coupled with a mixed-mode fracture criterion. The newly developed analytical model determines the interfacial shear and normal stress distributions as functions of the substrate curvature, during the various behavioral stages of the interface prior to the initiation of debonding. The model is also able to predict the debonding load and the effective bond length. In the numerical model the interface is modeled by zero-thickness node-to-segment contact elements, in which both the geometrical relationships between the nodes of the discretized problem and the interface constitutive laws are suitably defined. Numerical results and comparisons between the predictions of the two models are presented.

Behaviour of a masonry arch bridge repaired using fibre-reinforced polymer composites

“…This predicts that debonding occurs at a strain of 2430 µstrain for the north arch (with 3 strengthening plates), or 2164 µstrain for the south arch (with 6 strengthening plates). This result also agrees with the anchorage model by De Lorenzis and Zavarise [37], who demonstrated that the curvature does not significantly affect the load at the onset of peeling.…”

Coupled cohesive zone models for mixed-mode fracture: A comparative study

“…Despite the first models have been developed for single-mode fracture processes, cohesive fracture is expected to involve mixed-mode conditions, as observed in practice by experimental investigations performed on various types of lap joints [35], or interfaces between FRP sheets and flat [36,37] or curved substrates [38,39]. Mixed-mode CZMs can be classified as http://dx.doi.org/10.1016/j.engfracmech.2015.09.029 0013-7944/Ó 2015 Elsevier Ltd. All rights reserved.…”

Analytical model to predict the lifetime of concrete members externally reinforced with FRP

“…There are many models in the literature to calculate the s b distribution and their maximum, which is herein denoted by s bM [2][3][4]6,9,[11][12][13][14][15][16][17][18][19][20][21].…”

“…However, durability of a RC member externally reinforced with FRP depends not only on durability of the individual materials, but also on the capacity of the concrete cover to sustain the bond stresses s b [22][23][24][25]. In fact, on one hand, the FRP-composite material keeps its original strength, elasticity, and toughness [5,13,15,16,[26][27][28]; on the other hand, however, the combination of s b and initial cracks (flaws) in the concrete cover may give rise to slow crack growth up to the critical length, and eventually to debonding of the external reinforcement [29][30][31][32][33][34][35][36]. Unfortunately, neither the structural codes nor the structural practice considers explicitly the service failure that is caused by slow crack growth in the concrete cover.…”