seismic base isolation are devices that used to limit the human and material damage caused by an earthquake. this devices diffuse the energy induced at the time of the earthquake before being transferred to the structure.the base isolated structures when subjected to the near-fault eathquakes which contain long-period velocity pulses that may coincide with the period of base isolated structures...

It is impractical and uneconomic to design a structure that remains elastic throughout severe ground motions. The main design philosophy is that minor structural damages are acceptable as long as the structure does not collapse. Hence, seismic base isolation of structures provides a better alternative in constructing seismic resistant structures. A fixed-base structure designed in accordance to...

In this paper the semi-active control is achieved by a base isolation system. The magnetorheological dampers (MRD) hysteretic force is described by models based on nonlinear differential equation Bouc-Wen. The Bouc-Wen model is able to capture, in an analytical form, a range of shapes of hysteretic cycles which match the behavior of a wide class of nonlinear systems. In order to reduce the seis...

Seismic base isolation are devices that used to limit the human and material damage caused by an earthquake. This devices diffuse the energy induced at the time of the earthquake before being transferred to the structure.The base isolated structures when subjected to the near-fault eathquakes which contain long-period velocity pulses that may coincide with the period of base isolated structures...

Recent experimental research has shown that ordinary unbounded steel reinforced elastomeric bearings (SREBs) can be considered as an attractive cost-effective option for the seismic isolation of highway bridges. To further investigate its benefits, the current study is focused on the seismic risk assessment of an optimally designed highway bridge isolated by SREB system. A typical three-span hi...

The concept and theory of base isolation system are widely accepted at the present. To accomplish the predicted behaviours of the base-isolated buildings, the design for base isolation system is regarded as the dominant factor of the success of isolated buildings. Although the base isolation design can be fulfilled using Uniform Building Code 1997, conceptual design is yet necessarily analyzing...

endurance time (et) method is a relatively new performance-based earthquake method for structural evaluation and design. in this method, the structure is subjected to a gradually intensifying accelorogram(s) and its performance is assessed based on the maximum time duration that it can meet the specified performance objectives. using moment-resisting and braced frames which are rehabilitated by...

The base isolation systems are among the passive control devices that have been used over the last three decades to limit the seismic-induced response of structures. In this regard, the Uniform Building Code provisions (UBC) has incorporated a special section for the seismic design of base isolated structures since its 1991 edition. Due to the importance of the behavior of these structures unde...