Characterization of the Adhesive Layer through Finite Element Modeling in Double Strap Joints and Validation Through Digital Image Correlation

Abstract

The accurate measurement of strain on engineering structures is crucial for evaluating their performance and ensuring their structural integrity. Strain gauges are employed for this purpose, enabling to monitor mechanical deformations and stress distributions. The adhesive layer serves as a medium between the strain gauge and the material being tested. Changes in the adhesive layer can impact, and strain transfers between materials and strain gauges when subjected to different types of loading. The p study investigates the adhesive layer's role in strain gauge mounting on substrates through experiments, finite element analysis (FEA) and comparison of analytical model predictions (Volkersen and Tsai) with the experimental digital image correlation (DIC) results. Experiments are carried out for double strap joint samples and three-dimensional finite element analysis is carried out with aid of ANSYS software. FEA model is used to simulate the adhesive layer's mechanical behavior, taking into account material properties and boundary conditions determined through experimental characterization. DIC data are used to understand the strain transfer mechanism of the adhesive layer in strain gauge mounting. The findings from both the FEA and experimental studies highlight the significance of the adhesive layer's properties, in obtaining precise strain measurements and strain transfer mechanisms. A thorough comparison of FEA predictions with experimental results allows for identifying critical factors that influence the accuracy of strain gauge measurements using DIC adhesive layers. This study offers guidance for choosing suitable adhesive materials and ideal mounting configurations for particular application. © ASM International 2024.