Purpose <p>The study aims to investigate the nonlinear dynamic response of bolted joints with clearance-induced collisions.</p> Method <p>A hybrid analytical framework integrating the Iwan model and Hertz contact theory is used. A three-degree-offreedom dynamic model is developed to characterize the interplay of contact nonlinearity, gap interactions, and energy dissipation mechanisms. Numerical solutions of the governing equations reveal the influence of critical parameters.</p> Results and Conclusions <p>Small gaps induce strong nonlinear vibrations, while larger gaps reduce high-frequency components, making the system more linear.High collision stiffness leads to larger vibration amplitudes, whereas low collision stiffness results in a more linear system response.Higher excitation forces cause more intense vibrations, significantly increasing the amplitude of the main frequency component in the spectrum.Smaller gaps and higher stiffness reduce vibrations and improve stability, while larger gaps and lower stiffness cause significant vibration amplification at higher frequencies, indicating resonance-like behavior. The proposed model outperforms conventional approaches in capturing transient nonlinear transitions, offering a robust foundation for optimizing the reliability and performance of bolted joints in mechanical and aerospace applications. Careful parameter selection and optimized design can effectively enhance the dynamic performance of bolted joint structures.</p>