1. Characterization of NanoG
Measurement Report on Vibration Isolation of NanoG
Department of Physics, University of British Columbia, Vancouver PI: Dr Yan Pennec
Student: Vincent Wong

2. SolidWorks model – NanoG
Suspended by 6 isolators (Model #)
Volume: m3 Density: kg/m3 Mass: E4 kg %Concrete: 91.9%
Young Modulus: 4.38E10N/m2 Poisson Ratio: 0.17

3. Concrete Block Properties Deduction from Threshold Pressure
Isolator Dimension
Chamber Diameter: 27.6in
Total Effective Area: in2 * 6isolators
Threshold Pressure: 58psi
Threshold Supporting Force: lbf
Equivalent to N
Measured Mass: kg
Measured Density: kg/m3

4. Experiment Protocol - Slab Excitation
Reference Accelerometer
Data Point

5. Slab Excitation – Acceleration Amplitude
Time Constant ~91ms
y = A1*exp(-x/t1) + y0
y0= ms-2
A1= ms-2
t1= s

6. Slab Excitation – Average PSD (1-1kHz)

7. Slab Excitation – Average PSD (150-450Hz)
Twisting
Flapping
Support
Compressing
Bending

8. Resonance Mode - Twisting Mode
Measured 194Hz
FEA 193Hz
(1st mode in FEA)

9. Resonance Mode – Compressing Mode
Measured 197Hz
FEA 196 Hz
(2nd mode in FEA)

10. Resonance Mode - Bending Mode
Measured 294Hz
FEA 291 Hz
(3rd mode in FEA)

11. Resonance Mode – Bending Mode
Measured 309Hz
FEA 306 Hz
(4th mode in FEA)

12. Resonance Mode – Flapping Support Mode
Measured 346Hz
FEA 338 Hz
(5th mode in FEA)

13. Resonance Mode – Twisting Support Mode
Measured 366Hz
FEA 369 Hz
(6th mode in FEA)

14. Resonance Mode – Twisting Mode
Measured 377Hz
FEA 376 Hz
(7th mode in FEA)

15. Resonance Mode – Twisting Mode
Measured 388Hz
FEA 386 Hz
(8th mode in FEA)

16. Resonance Mode – Twisting Support Mode
Measured 420Hz
FEA 415 Hz
(10th mode in FEA)

17. Resonance Mode – Sideway Bending Mode
Measured 458Hz
FEA 450 Hz
(13th mode in FEA)

18. Damping by Isolators – x-axis acceleration amplitude
Time Constant ~ 37.7s
Natural Frequency ~ 0.65Hz
y = A1*exp(-x/t1) + y0
y0= E-5 ms-2
A1= E-4 ms-2
t1= s

19. Damping by Isolators – y-axis acceleration amplitude
Time Constant ~ 29.8s
Natural Frequency ~ 0.65 Hz
y = A1*exp(-x/t1) + y0
y0= 9.396E-4 ms-2
A1= ms-2
t1= s

20. Damping by Isolators – z-axis acceleration amplitude
Time Constant ~ 476ms
Natural Frequency ~1.3Hz
y = A1*exp(-x/t1) + y0
y0= -5.08E-4 ms-2
A1= ms-2
t1= s

21. Transfer Function - Isolators

22. Transfer Function in z-axis – Room Isolation

23. Seismic Vibration in z-axis – velocity PSD open room

24. Seismic Vibration in z-axis – velocity PSD closed room (1 hour run)

25. Sound Pressure Level – closed room

26. Sound Pressure Level – Excited
22Hz
42Hz
34Hz

27. Acoustic Resonance Assumption: speed of sound = 350m/s
Expected Resonance Mode:
3.5m -> ~50Hz
5.8m -> ~30.2Hz
7.6m -> ~23Hz
6.8m -> ~25.7Hz
8.4m -> ~20.8Hz
9.6m -> ~18.2Hz
10.2m -> ~17.2Hz