If the surrounding rock with strain softening and
shear dilation effect can be supported in reasonable time, it will be good for
deepburied tunnel to keep stable and save cost. Based on convergenceconfinement method, a twostage analysis
method of surrounding rocksupporting interaction is
proposed, and yield axial force of primary support and reduction rate of
surrounding rock deformation are introduced to determine reasonable support
time. Then, based on threedimensional finite
difference software, yield axial force of primary support and reduction rate of
surrounding rock deformation are explored, and the reserved deformation range
under the influence of different surrounding rock quality, support type,
initial stress, critical plastic softening coefficient, and shear dilation
angle is analyzed. The results indicate that: (1) The rock mass quality and
initial stress have significant impact on the support time of the tunnel, but
that of the postpeak shear dilation and strain
softening behaviors is small. (2)For the rock mass with ideal elasticplastic or unobvious shear dilation,
internal support is beneficial to maintaining rock mass stable, which cannot
only reduce the stress release of rock mass, but also improve the deformation
control effect of surrounding rock.
TANG Xiongjun
. Reasonable Support Time for Deep-Buried
Tunnel Considering Strain Softening and Shear Dilation
Effect of Surrounding Rock[J]. Tunnel Construction, 2021
, 41(S2)
: 190
-198
.
DOI: 10.3973/j.issn.2096-4498.2021.S2.024
