Nonlinear Response of an Articulated Offshore Loading Platform

Summary

Project Title:

Prinicipal Investigators:

Jack Lou

Sponsor:

National Science Foundation

Completion Date:

June, 1990

Final Report:

A2 (Click to view final report abstract)

Scope of Work:
The primary interests of this research are to investigate the applicability of the classical dynamic theory and to develop approximate analytic and efficient numerical methods for the study of dynamic behavior of a strong nonlinear offshore system. Since this study concerns a highly nonlinear system, the analysis will start with the investigation of local behavior including equilibrium points, stability analysis, and subharmonic and superharmonic resonances. For the large response, the global behavior will be studied using analytical and numerical methods to identify the possible existence of parametric ranges that will result in chaotic motions.

The objectives of this research were:

to develop SDOF and 2-DOF models for an ALP-tanker system including fluid/structure interaction effects.
to investigate the applicability of classical dynamic theory on the strong nonlinear offshore system,
to develop an approximate analytical method for analyzing strong nonlinear systems,
to develop an efficient numerical simulation method capable of analyzing the piecewise-nonlinear system,
to determine the effects of initial conditions and system parameters on the dynamic behavior of the system,
to determine the possible existence of chaotic motions and
to provide a foundation for the future research on chaotic motions of more complex compliant structures.

Related Publications:
Choi, H.S. and Lou, J.Y.K. “Non-linear Behavior and Chaotic Motions of an SDOF System With Piecewise-Non-Linear Stiffness” Int. J. Non-Linear Mechanics, Vol.26, No. 5, pp. 461-473, 1991.