1. Fifth Tongji-UBC Symposium on Earthquake Engineering REN Xiangxiang Research Institute of Structural engineering and Disaster Reduction 2015/05/04 Dynamic Similitude Mechanism and Design of Base-isolated Model

2. Fifth Tongji-UBC Symposium on Earthquake Engineering 1. Similitude Mechanism of Base-isolated Structures Structures Outline 2. Design Procedure of a Base-isolated Building Model Building Model 4. Conclusion 3. Model Construction and Testing

3. Fifth Tongji-UBC Symposium on Earthquake Engineering 1. Similitude Mechanism of Base-isolated Structures Shanghai Oriental Pearl Tower Shanghai Tower Similitude

4. Fifth Tongji-UBC Symposium on Earthquake Engineering Similitude Design Similitude Relation Loading PrototypeModel Test Results Reinforced structures steel structures Base-isolated Stress-strain property during the elastic stage Bearing capacity of the critical elements The matching material Connections in small size Typical nonlinear performance 1. Similitude Mechanism of Base-isolated Structures

5. Fifth Tongji-UBC Symposium on Earthquake Engineering Structure ElementMaterial Cross section of the critical element The mechanical characters of different media interface 1. Similitude Mechanism of Base-isolated Structures

6. Fifth Tongji-UBC Symposium on Earthquake Engineering Structure Element Material Base-isolated Structures? 1. Similitude Mechanism of Base-isolated Structures Structure-based similitude method

7. Fifth Tongji-UBC Symposium on Earthquake Engineering Structure-based similitude method ---the structural property and dynamic responses of the model structure keep being similar to that of the prototype structure under actions of earthquake in different level. 1. Similitude Mechanism of Base-isolated Structures

8. Fifth Tongji-UBC Symposium on Earthquake Engineering Isolation bearing arrangement Isolate layer Global structure Superstructure Transfer layer 2. Design Procedure of a Base-isolated Building

9. Fifth Tongji-UBC Symposium on Earthquake Engineering 2. Design Procedure of a Base-isolated Building

10. Fifth Tongji-UBC Symposium on Earthquake Engineering Superstructure 1/4 The prototype The model 2. Design Procedure of a Base-isolated Building

11. Fifth Tongji-UBC Symposium on Earthquake Engineering Similitude Theoretical model Transfer layer The prototype Problems ：  Insufficient stiffness  Less bearings ， insufficient overturning resistance ？ 2. Design Procedure of a Base-isolated Building

12. Fifth Tongji-UBC Symposium on Earthquake Engineering Transfer layer Theoretical modelActual model  Increase the stiffness of transfer beam  Increase the transfer layer resistance to overturning 2. Design Procedure of a Base-isolated Building

13. Fifth Tongji-UBC Symposium on Earthquake Engineering Isolate layer Taking horizontal stiffness of the isolated layer as the basic similitude factor 6 rubber laminated bearings 12 elastic sliding bearings 4rubber laminated bearings 4 elastic sliding bearings 2. Design Procedure of a Base-isolated Building

14. Fifth Tongji-UBC Symposium on Earthquake Engineering 振动台试验 Forms of the transfer layer Concrete placing Curing of the concrete Building the wall of the first floorWall of the first floor The global model 3. Model Construction and Testing

15. Fifth Tongji-UBC Symposium on Earthquake Engineering Shaking table test Seismic intensity: 7 degree Seismic excitation:  El-Centro wave  Wenchuan wave  Pasadena wave  Shanghai wave 3. Model Construction and Testing

16. Fifth Tongji-UBC Symposium on Earthquake Engineering Frequency and mode of the prototype and the model 3. Model Construction and Testing

17. Fifth Tongji-UBC Symposium on Earthquake Engineering Peak values of acceleration under Pasadena wave Frequent earthquake Basic earthquake Rare earthquake  Maximum acceleration distribution are in good agreement;  Peak value of the model is bigger than that of the prototype. 3. Model Construction and Testing

18. Fifth Tongji-UBC Symposium on Earthquake Engineering Frequent earthquake Basic earthquake Rare earthquake Acceleration response history under Pasadena wave  Acceleration response of the basic earthquake is in good agreement with the rare earthquake  Values of the model are bigger than that of the prototype under frequent earthquake. 3. Model Construction and Testing

19. Fifth Tongji-UBC Symposium on Earthquake Engineering 4. Conclusion (1) Existing similitude approaches are classified into three levels, including the material level, the elemental level and the structural level. (2) Model of the base-isolated structures are scaled down based on similitude approach in structural level. (3) The similitude between the model and the prototype is greatly improved compared to the traditional similitude approach.

20. Fifth Tongji-UBC Symposium on Earthquake Engineering