Equivalent Spring Modeling of Bolted Connections to Streamline Dynamic Modeling

open_access
Open Access
Author:
Mc Gowan, Douglas
Area of Honors:
Mechanical Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Matt Lear, Thesis Supervisor
Jean-Michel Mongeau, Thesis Honors Advisor
Keywords:
spring
modeling
dynamic
bolt
joint
coupling
analysis
Abstract:
This thesis presents a novel approach to modeling bolted connections using spring elements, providing a computationally efficient alternative to explicit contact modeling. Traditional methods for analyzing bolted assemblies often use detailed finite element representations, which can be computationally expensive and impractical for iterative design processes. The proposed 6-DOF spring model captures the stiffness characteristics of bolted joints across all degrees of freedom, offering comparable accuracy to explicit models without requiring experimental data. The study incorporates both composite and steel in a bolted double lap joint assembly. Static simulations are used to extract stiffness parameters for the bolted joint, which are then applied in the spring model. By comparing the dynamic responses of the explicit and springbased models, this work evaluates the trade-offs between computational efficiency and accuracy. Results indicate that the spring model achieves a 551.7% reduction in computational time while maintaining an average natural frequency error of 1.5% relative to the explicit model. Additionally, the spring model effectively predicts mode shapes, low-frequency response, and vibration transmission with acceptable accuracy. This research addresses gaps in bolted joint modeling research, including the need for multi-material configurations, realistic loading conditions, and comprehensive dynamic response analysis across all six degrees of freedom. The findings contribute to the development of adaptable, simulation-informed design methodologies for bolted assemblies. The efficiency and versatility of the proposed method demonstrate its potential for broader adoption in dynamic structural analysis.