Experimental and analytical study of the dynamic debonding in FRP plated beams

Abstract

a b s t r a c tThis paper presents an experimental study of the dynamic debonding failure mechanism in FRP plated beams. The experimental study is accompanied by an analytical/numerical study. The focus in the experimental investigation is on the dynamic aspects of the brittle, rapid, and abrupt failure mechanism and on its characterization and quantification. The experimental technique is based on four point bending tests of FRP plated steel beam specimens. The main dynamic monitoring technique uses high-speed digital photography with rate of 88,050 frames per second. The analytical and numerical aspects of the investigation use an extended high order layered beam theory with a physical modeling resolution that considers nucleation and evolution of the debonding mechanism in each physical interface. This is achieved by using cohesive interfaces and a specially tailored finite element formulation that is based on the theory. Digital image processing of the experimental results reveals and quantifies the dynamics of the interfacial failure with propagation velocities in the order of 100-1000 m/s and duration of less than 0.2 ms. The results reveal the dynamic nature of the failure process and provide an experimental benchmark for its consideration. They also provide direct experimental data for supporting and validating the theory and for determining the fracture energy and length scale parameters of the cohesive interfaces. With that, the combined experimental and theoretical study further explores the dynamic features of the failure mechanism.

A 4pt bending bond test approach to evaluate water effect in a composite beam

“…As explained and illustrated in details in (Chabot et al, 2013a(Chabot et al, , 2013b, according to the principles of linear elastic fracture mechanics, from the sign of the derivative of energy release with respect to the crack length, the crack is expected to propagate initially along the interface in a unstable way before this propagation becomes stable from a given crack length value (function of the values of the materials and the geometry of the specimen). The instable part of this propagation has been specifically illustrated very recently on two specimens only, by means of a high-speed digital photography (Mulian & Rabinovitch, 2016).…”

Dynamic debonding in layered structures: a coupled ALE-cohesive approach

“…3-6, respectively. In the present study, comparisons with results arising from the literature [18,19] are developed. The main model refers to a steel beam, strengthened with FRP strip elements.…”

Feasibility of Repairing Concrete with Ultra-High Molecular Weight Polyethylene Fiber Cloth: A Comprehensive Literature Review

“…Its excellent strain-hardening capacity makes strong energy absorption [44,45]. In contrast, other FRP materials are susceptible to detachment and breakage from concrete matrix under high-displacement dynamic loads, such as earthquakes [46][47][48][49][50].…”