Conventional analytical
methods for tunnel seepage fields－such
as the mirror method, well-flow theory, and conformal
transformation－are limited to single-layer geological structures. To overcome this limitation, the tunnel
seepage field in stratified rock masses is decomposed into three components:
the vertical unidirectional seepage field of the rock strata, the radial
seepage field in the surrounding rock, and the radial seepage field in the
tunnel lining. Based on groundwater dynamics and the complex potential function
theory, the governing equations for each component are independently solved.
Subsequently, the analytical solution for the overall seepage field under
stratified rock mass conditions is derived using appropriate boundary
conditions. The validity of the analytical solution is confirmed through
numerical simulation of a representative engineering case. The analytical
solution is further used to investigate the influence of layer thickness and
permeability coefficients on tunnel seepage flow and the external water
pressure acting on the tunnel lining in stratified rock environments. The
results indicate that in tunnels overlain by strata with high permeability in
the upper layers and low permeability in the lower layers, the thickness and
permeability of the weakly permeable layer in which the tunnel is embedded
critically control both the seepage flow and external water pressure. This
phenomenon arises because the low-permeability layer acts
as a relatively impermeable barrier within the stratified rock mass. Variations
in its thickness and permeability significantly impact tunnel seepage behavior
and lining water pressure.
ZHANG Ning
,
LI Zhensong
,
ZHANG Haoran
,
ZHANG Xiaoping
,
LI Ningxin
.
Analytical Solution of Tunnel Seepage Field Under Environment of Rock Mass Characteristic Stratification
[J]. Tunnel Construction, 2025
, 45(6)
: 1142
-1153
.
DOI: 10.3973/j.issn.2096-4498.2025.06.009
