ANALYSIS OF THE EFFECT OF SECONDARY BENDING ON SINGLE LAP JOINT JOINTS USING ADHESIVE ELEMENTS

• Main Author: Demas Priambudi, Oktavianus
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/77971
• Institution: Institut Teknologi Bandung

In the aerospace industry, the use of adhesives in the manufacture of fuselage and wing structures has been applied for more than 60 years. Adhesive connections offer several advantages over mechanical connections. These advantages are the ability to connect two different types of materials, a more uniform stress field along the connection area, and lighter due to the absence of bolts or rivets. One adhesive joint design is the single lap joint (SLJ). Such types of joints are widely used due to their simple geometry and high structural efficiency. However, the main drawbacks of this type of connection are the load eccentricity that causes secondary bending in the joint area and the unexpected normal stress along the adhesive edge. In this study, finite element method analysis was carried out with a cohesive zone model (CZM) approach to see the influence of secondary bending in different cases (geometry cases, adhesive thickness cases, and connection length cases). The result obtained is the distribution of normal and shear stress along the connection. The results will be processed to obtain the stress ratio and find the relationship with the shear strength of the joint. From the analysis, it was found that the modeling results were quite accurate with the difference in results between the numerical method and the experimental method valued at 5.43%. For the case of geometry configuration adherend adhesive chamfer has the highest maximum load of 10171 N. Then for the case of adhesive thickness, the thinner adhesive will have the highest maximum load of 8984 N at 0.2 mm thick. Then for the case of adhesive length, the longer adhesive will have the highest maximum load of 13126 N at a length of 100 mm. However, the strength of its shear force will decrease. From there, the optimal configuration for SLJ with AV138 adhesive (brittle adhesive) is a configuration with adherend chamfer geometry, thin adhesive thickness, and short adhesive length.