Optimizing Joint Parameters for Enhanced Strength in Bolted Natural Fiber Reinforced Polymer Composite Assemblies

  • Amol Dnyaneshwarrao Sable VTU Research Scholar
  • Dr R.P. Swamy Research Supervisor VTU, UBDT, Davangere
  • Dr R.P. Swamy Research Supervisor VTU, UBDT, Davangere
Keywords: Natural fiber composites, bolted joints, joint optimization, bearing strength, failure mode analysis, torque– washer interaction

Abstract

NFRP composites Natural Fiber Reinforced Polymer composites are increasingly emerging as eco-friendly replacements of synthetic based structural composites. Mechanical joining however poses special problems because of the anisotropic and brittle character of NFRPs and these types of joining tend to result in premature failure through delamination or shear-out. The paper examines the effect of the most important parameters of joints, such as the bolt diameter, the size of washers, torque, hole fit and edge distance, on the behaviour of bolted joints in NFRP laminates. Hand lay-up production of composite specimens by using natural fibers and epoxy resin together with their testing to ASTM D5961 standards was done. Results of the experiments showed that the best joint strength was achieved when the bolt diameter was 10mm, the washer was big (24mm outer diameter), holes were tight-fitting, and the torque was 10Nm and the edge distance was at least 3D. Optimization (based on Taguchi) indicated that the most marked variables were torque and washer size with a high interaction. The favourable transition of failure to bearings during optimization was ascertained by failure mode analysis. The results help in the designing codes to improve integrity of joints in long-lived composite constructions.

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Published
2025-12-10
How to Cite
Sable, A., Swamy, D. R., & Swamy, D. R. (2025). Optimizing Joint Parameters for Enhanced Strength in Bolted Natural Fiber Reinforced Polymer Composite Assemblies. Asian Journal For Convergence In Technology (AJCT) ISSN -2350-1146, 11(1), 82 - 87. https://doi.org/10.33130/AJCT.2025v1101.011

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