Abstract:

In recent years, scholars around the world have shown increasing interest in elastic support structures, leading to significant progress in dynamic modeling techniques for pipeline systems. Although multiple analytical approaches exist, engineers increasingly prioritize computationally efficient, precise low-order models for practical implementation. In order to address this need, this study develops an innovative nonlinear dynamic formulation for pipelines accounting for both foundation and boundary nonlinearities. The proposed solution methodology initiates with global mode extraction using the global mode technique, followed by a detailed implementation procedure. Model validation is conducted through a cantilever pipeline case study featuring nonlinear support conditions, where strong agreement between the proposed model’s predictions and finite-element benchmark solutions demonstrates its reliability. Subsequently, a comprehensive parametric study investigates the combined effects of foundation stiffness, boundary constraints, excitation intensity, and nonlinear interaction terms on the vibrational response of the cantilever pipe. This systematic approach yields critical insights for practical engineering designs and applications.

Key words: fluid-conveying pipeline, complex constraint, nonlinear dynamics, global modal method