Abstract:
As for the <2-5> medium-fine sand stratum, in which the shield tunnel section of Fuzhou Metro Line 5 along Minjiang River locates, the small shaking table tests are performed under 9 orthogonal design conditions to explore the liquefaction characteristics of Minjiang sands. The results show that the excess pore water pressures and excess pore water pressure ratios at different depths quickly accumulate to the peak values in the initial excitation stage, then drop slightly and finally remain stable until the end of the excitation; the influence degrees of various factors on liquefaction of sands are ranked as follows: input wave amplitude>input frequency>soil saturation; for the sand stratum at shallow depth, it has higher liquefaction possibility, and slight, medium and complete liquefaction events might occur under action of designed earthquake, rare earthquake and huge earthquake, respectively. The test results can provide a basis for the parameter calibration in subsequent numerical simulations and a reference for engineering construction along the Minjiang River.
NING Maoquan1,
2 XIAO Mingqing1 JIN Xuehui1,
2 ZHAO Liya1 etc
.Study on Liquefaction Characteristics of Medium-fine Sands in Shield Tunnelling with Small-size Shaking Table Test[J] MODERN TUNNELLING TECHNOLOGY, 2021,V58(4): 178-184