GUAN Zhen-chang, GONG Zhen-feng, LUO Zhi-bin, et al. Seismic property of a large section tunnel based on shaking table model tests[J]. 2016, 37(9): 2553-2560.
DOI:
GUAN Zhen-chang, GONG Zhen-feng, LUO Zhi-bin, et al. Seismic property of a large section tunnel based on shaking table model tests[J]. 2016, 37(9): 2553-2560.DOI: 10.16285/j.rsm.2016.09.016.
Seismic property of a large section tunnel based on shaking table model tests
a 1/30 model for a large section tunnel is firstly designed based on the extension project of Jinjishan Tunnel along Fuzhou 2nd ring road. Then the earthquake-simulating tests are conducted under 21 different loading conditions using a bidirectional earthquake shaking table apparatus at Fuzhou University. Through Fourier analysis of testing results
it indicates that the existence of the large section tunnel changes the seismic property of original ground significantly. It is also found that the 1st predominant frequency reflects the seismic properties of original ground
while the 2nd predominant frequency demonstrates seismic properties of the lining structure. The frequency-response analysis of testing results shows that the components augment significantly around the 2nd predominant frequency
when the seismic wave propagates from the bottom to top until the lining structure. The most-augmented frequency almost equals to the 2nd predominant frequency. The relationship between the seismic property of the large section tunnel and the amplitude of input ground motion is studied in detail. The apparent cracks emerge on the lining structure after the excitation by the large ground motion
which significantly reduces the overall stiffness of the large section tunnel. Moreover
both the 2nd predominant frequency and the most-augmented frequency show remarkable reductions. In conclusion
this study provides some useful suggestions for the earthquake fortification of the large section tunnel.