Seismic Base Isolater

This model is to represent the working of a seismic base isolator.

Seismic base isolation, is one of the most popular way of protecting a structure against earthquake force. As the foundation of the structure is connected to the structure, so during the earthquake, due to movement of the ground, the structure also starts shaking with it and it damages the structure. But, there is one way in which the connection can be separated. By using seismic base isolators, the forces of earthquake can be resisted almost. In this process, the isolators are placed between the foundation and column of the structure. This isolators absorbs the shocks of the earthquake, therefore energy transferred to the structure is very less, hence helping the structure from damage, internally and externally also.

Isolators in constructed of circular shape, in which the outer surface consist of laminated rubber. In centre, there is lead core which acts as energy dissipating. Remaining part is consisted of rubber layer reinforced steel.

The outer rubber layer acts as a spring. It is very soft laterally and very stiff vertically. This high vertical stiffness is obtained due to thin rubber layers. Due these two characteristics, it allows the isolator to move laterally with relatively low stiffness yet carry significant axial load due to their high vertical stiffness.

In this model, we have constructed two wooden structure, representing two building, of different floors and tried to create an earthquake scene in it by placing those wooden structure on a table and impacted shock wave, by shaking the table. But in one of the wooden structure, a replica of isolator is kept, which will work exactly as an isolators. As the table is being shake, the building with no isolator, will have a large amount of effect of shake. Whereas, the building with isolator, will have very minimum effect of shake.

Such type of isolators can be used in such areas, where shocks of earthquakes are frequent and are of high reactor scale. And even in such structures, where emergency situation arise after shock of earthquake for example hospitals, fire stations. Such places are places, where the damage due to the shocks of earthquakes is very crucial.

Hence, by providing such isolators to the structures, even during the shocks, the structure can be operational. But, due to high costing material is used in isolators, it cannot be used by any person, since it would be requiring high amount of investment.

After the sever earthquake in Bhuj 2001, a four storeyed hospital is built in Bhuj city by using the technique of seismic base isolators.

Seismic base isolator model has won the first prize in MODEL MAKING COMPETITION, of Engineers Day Celebration, conducted in Amiraj College. Even, it has also banged Second Rank in TECH FEST, which was conducted by GTU in SAL College.
Names of participant:-

1. Divyaraj Mahida (131080106012)
2. Kandarp Majmudar (131080106024)
3. Kartik Patel (131080106040)
4. Ishit Patel(131080106039)
5. Nilpa Ahalpara(131080106003)