S. M Atifeh - Undergraduate Student, School of Mechanical Engineering, Iran University of Science & Technology, Tehran, Iran
M. M Shokrieh - Professor, School of Mechanical Engineering, Iran University of Science & Technology, Tehran, Iran
A.R Shamaei-Kashani - Ph.D. student, School of Mechanical Engineering, Iran University of Science & Technology, Tehran, Iran

Abstract- In this research, a new finite element based model is presented to predict the stiffness of single-lap multi-boltcomposite joints. The model uses stiffness of a single-lap single-bolt joint and geometrical parameters such as thickness,length, width of composite laminates and diameter and number of bolts. First, a numerical model was proposed byABAQUS finite element software to calculate stiffness of a single-lap single-bolt composite joint. Then, using the stiffnessof the single-lap single-bolt composite, material and geometrical parameters of multi-bolt joint, the stiffness of the singlelapmulti-bolt composite joint was calculated. By comparing the results of the proposed model with experimental andnumerical data, it was observed that the new model estimates the stiffness of the single-lap multi-bolt joint with a very goodaccuracy. The maximum error of the model is about six percent.

Bolted Composite Joints, Stiffness, Finite Element Method, Single Lap Joints