Fig. 1. Design of prototype abutment
Fig. 2. Prototype abutment
Fig. 3. Mode number of abutment
Fig. 4. Instrument equipment and impact hammer
Fig. 5. Experiment process of prototype abutment
Fig. 6. Schematic view of instrument position and impact direction
Fig. 7. Time - acceleration history
Fig. 8. Calculation of natural frequency
Fig. 9. Calculation of phase
Fig. 10. 1th mode of prototype abutment (Surcharge load 0 tonf)
Fig. 11. Phase difference of prototype abutment (1th mode)
Fig. 12. 2nd mode of prototype abutment (Surcharge load 0 tonf)
Fig. 13. Phase difference of prototype abutment (2nd mode)
Fig. 14. 3rd mode of prototype abutment (Surcharge load 0 tonf)
Fig. 15. Phase difference of prototype abutment (3rd mode)
Fig. 16. 4th mode of prototype abutment (Surcharge load 0 tonf)
Fig. 17. Phase difference of prototype abutment (4th mode)
Fig. 18. Numerical analysis condition of scour progression
Fig. 19. Variation of natural frequency according to scour progression
Fig. 20. Variation of natural frequency according to surcharge load (1th ~ 4th mode)
Table 1. Natural frequency formula
Table 2. Eigenvalue of abutment and election of impact direction
Table 3. Experiment case of prototype abutment
Table 4. Comparison of natural frequency by mode number
Table 5. Natural frequency by mode number according to scour progression
References
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