To study the variations and distribution
characteristics of excess pore water pressure during shield tunneling in waterrich
silty fine sandy stratum and explore the influence of excess pore water
pressure on the limit support pressure of excavation face, the constrained
nonlinear function is calculated using the limit equilibrium method, and a
modified formula for calculating the limit support pressure is proposed based
on field test data of a largediameter rivercrossing shield tunnel project. The study shows the following: (1)
During shield tunneling, the disturbance area of pore water pressure is roughly
twice the excavation diameter ahead of the excavation face and 1.5 times the
excavation diameter on both sides of the excavation face; the closer to the
excavation face, the greater the disturbance degree. (2) The excess pore water
pressure has a great impact on active failure limit support pressure of
excavation face, thus, the slurry pressure should be appropriately increased,
or the whole slurry balance mode should be adopted to maintain the stability of
the excavation face and reduce the disturbance range and degree of pore water
pressure.
CHEN Xiangyu
,
PAN Xi
,
DING Jianjun
. Study on Influence of Excess Pore Water Pressure on
Limit Support Pressure of Shield Tunnel[J]. Tunnel Construction, 2021
, 41(4)
: 597
-603
.
DOI: 10.3973/j.issn.2096-4498.2021.04.009
