Experimental performance verification of rubber friction bearing

To reduce earthquake damage, the most commonly used seismic isolation systems since the 20th century employ a seismic isolator to support superstructures and reduce the effects caused by earthquakes. However, these seismic isolators have limitations such as shear failure and the falling-off of elemental parts when a large displacement occurs owing to an earthquake. There-fore, in this study, a rubber friction bearing (RFB) with improved structural performance was proposed to prevent the deterioration of and damage to structures and devices and to secure seismic stability. RFB is new concept device that improved load and deformation resistance performance, restoring force, and damping force by applying new materials and improving the structural shape. To verify the structure and seismic performance of the RFB, the theoretical behavior mechanism and design details were completed, and shear-characteristic and dynamic experiments were conducted. The experimental specimens were fabricated with shear moduli of 0.45 MPa and 0.90 MPa, and shear-characteristic experiments were conducted to verify whether the structural behavior characteristics reflect that in the theory and design. By analyzing the characteristics such as the yield strength, secondary stiffness, effective stiffness, and energy dissipation capacity based on the behavioral characteristics, the proposed RFB was verified to exhibit sufficient design capacity and structural performance. Additionally, to verify the practical seismic performance of the RFB, a dynamic experiment was performed using ground accelerations of 0.5 g, 0.6 g and 1.8 g, and the acceleration damping rate and allowable maximum displacement were analyzed to verify the practical seismic performance of the RFB. Consequently, all the specimens showed stable response results in the acceleration damping rate and the allowable maximum displacement. Thus, the RFB is verified to exhibit excellent structural seismic perfor-mances in terms of the load resistance, damping force, restoring force, and energy dissipation capacity.

Automated summary

This study proposes a rubber friction bearing (RFB) with improved structural performance to prevent deterioration and damage to structures and devices, and ensure seismic stability. The theoretical behavior mechanism and design details of the RFB were verified, and shear-characteristic and dynamic experiments were conducted. The results show that the RFB exhibits excellent structural seismic performance in terms of load resistance, damping force, restoring force, and energy dissipation capacity.