Date of Award


Publication Type

Master Thesis

Degree Name



Civil and Environmental Engineering

First Advisor

Shaohong Cheng


Damper stiffness, Damper support stiffness, Negative stiffness damper, Stay cables, Vibration control




Due to the superior performance of negative stiffness damper (NSD), its application to the vibration control of bridge stay cables attracts much research attention in recent years. Nevertheless, the effect of various system parameters on NSD performance has not been fully studied, especially the impact of damper support stiffness. In the current study, an experimental study on the dynamic response of a cable-NSD system is conducted to investigate the effect of negative damper stiffness and damper support stiffness on the efficiency of NSD. A numerical simulation is performed to not only validate the experimental results, but also evaluate the influence of various system parameters on NSD performance. A NSD design tool is developed to predict optimum damper size and the corresponding maximum achievable modal damping ratio of a cable-NSD system. Results show that when the stability criterion is satisfied, choosing stronger negative damper stiffness would enhance NSD efficiency. The impact of support stiffness on NSD performance depends on the magnitude of damper stiffness. Attach a NSD to a cable having larger sag and/or higher bending stiffness would yield a lower maximum achievable system modal damping ratio.