The effect of positioning of seismic isolators in a reinforced concrete building

Abstract

Construction costs are increasing day by day. The importance of building the safest structures at the lowest cost is also increasing. For this purpose, it is necessary to design the structure in the best possible way without sacrificing safety. One way to ensure buildings are safe even during severe earthquakes is to include seismic isolation at the design stage. Judging by studies, seismic isolators are generally located at the lowest story of the building. However, there is no sufficient study to determine the location of the seismic isolator in the lowest column. In this study, the seismic isolator was located at the lower end and the top of the lowest story of the RC building to compare the effectiveness of its positioning. A high-damping rubber bearing (HDRB) was used as the seismic isolation device. Also, the effect of the absence of the diaphragm placed above the isolation level was investigated. As a result of the study, the necessary rebar of the RC building isolated at the top end of the column was less than 15% compared to the building isolated at the lower end of the columns for the beams. The base shear force of the building with seismic isolator located at the upper end of the column was 2.7% greater than that the building with the seismic isolator located at the lower end of the column.

Keywords

• HDRB design
• UBC97
• Isolator device positioning
• Reinforced cocncrete building
• Finite elements model

The effect of positioning of seismic isolators in a reinforced concrete building

Abstract

Construction costs are increasing day by day. The importance of building the safest structures at the lowest cost is also increasing. For this purpose, it is necessary to design the structure in the best possible way without sacrificing safety. One way to ensure buildings are safe even during severe earthquakes is to include seismic isolation at the design stage. Judging by studies, seismic isolators are generally located at the lowest story of the building. However, the location of the seismic isolator on the lowest column has not been defined. In this study, the seismic isolator was located at the lower end and the top of the lowest story of the RC building to compare the effectiveness of its positioning. A high-damping rubber bearing (HDRB) was used as the seismic isolation device. Also, the effect of the absence of the diaphragm placed above the isolation level was investigated. As a result of the study, the necessary rebar of the RC building isolated at the top end of the column was less than 15% compared to the building isolated at the lower end of the columns for the beams. The base shear force of the building with seismic isolator located at the upper end of the column was 2.7% greater than that the building with the seismic isolator located at the lower end of the column.

Keywords

• HDRB design
• UBC97
• Isolator device positioning
• Reinforced concrete building
• Finite elements model

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