摘要: |
The process of monitoring structural health and identifying damage severity and location is generally termed structural health monitoring (SHM). The core of this project is to investigate how variable stiffness and damping devices (VSDD) can be most effectively used to identify local damage in bridge and building structures. Using one or more VSDDs to modify the response, simulated damage is detected, localized, and quantified. One fundamental goal is to determine the best VSDD actions-whether adding damping or stiffness-to precisely and robustly locate and identify bridge damage. This study is based on simulation of bridge motion and other structures due to ambient excitation sources. Several VSDD behaviors, such as variable stiffness mode and variable damping mode, are studied in the context of a frequency domain analysis. These analyses are performed on simple models of bridge and building dynamics, e.g., two degree-of-freedom (2DOF) shear model systems and a six degree-of-freedom (6DOF) model. Structural behavior is assumed locally linear before damage and after damage. Generally, VSDDs were successful in improving the damage identification in structures using the variable stiffness mode but rather unsuccessful in the variable damping only mode. In addition to demonstrating the potential of using variable stiffness and damping devices to improve structural health monitoring, this study also provides some insights into further avenues of future research to build on the improvements studied herein. |