Modeling of a Highly Damped Natural Rubber Elastomeric Bearing for Seismic Base Isolation Purposes
Open Access
- Author:
- Florian, Matthew Scott
- Area of Honors:
- Mechanical Engineering (Behrend)
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Oladipo Onipede Jr., Thesis Supervisor
Amir Khalilollahi, Thesis Honors Advisor - Keywords:
- Elastomeric Bearing
Seismic Base Isolation
ANSYS Modeling
Highly Damped Rubber - Abstract:
- Seismic base isolation is widely used as a method for limiting the damage caused to buildings, bridges, and other structures during a seismic event. Currently, one of the most popular methods of achieving seismic base isolation is to insert elastomeric bearings at the foundation of a structure. Several types of elastomeric bearings exist, including low damping natural rubber, high damping natural rubber, and lead plug bearings. These bearings achieve seismic base isolation by allowing the structure to move horizontally while maintaining the vertical load carrying capacity needed to support the weight of the structure. Several parameters are important when selecting an elastomeric bearing for various applications. This research project aims at analyzing the most important geometric parameters for the high damping natural rubber bearing. These parameters were analyzed using ANSYS Workbench and their effects on the vertical and horizontal natural frequency of the elastomeric bearing were determined. The goal of this modeling is to determine the optimum parameters necessary to obtain the most successful elastomeric bearing. The effects of the isolation system were further analyzed through modeling of a five story building in ANSYS Workbench. After modeling an isolated and un-isolated building, the effects of the elastomeric bearings were clearly evident. The isolated building was clearly able to move horizontally at a much lower frequency while still maintaining a vertical frequency close to that of the un-isolated building.