In cold regions, frostheaving
phenomenon often occurs due to the phase change of pore water in the
surrounding rock of a hydraulic tunnel under the influence of low temperature.
First, a thermohydromechanical
coupling model for Bulunkou hydropower station in Xinjiang is established using
numerical simulation software based on the theory of elastoplastic mechanics
and by considering the change in the thermodynamic parameters of the
surrounding rock due to the low temperature waterice
phase change. Subsequently, the elastoplastic frostheaving
force solution of the surrounding rock, transient temperature field, frostheaving stress, and surroundingrock
displacement are calculated. Finally, the change patterns in the frost depth
and the stress and deformation before and after frost heaving are obtained
through analysis. The results show the following. (1) The pore water of the
surrounding rock undergoes a phase change under low temperature, and the
freezingcircle moves to the interior of the
surrounding rock over time. The freezing depth increases with time, and the
maximum freezing depth is 2.04 m under 200 days of freezing. (2) The calculated
stress of the surrounding rock is between 0.392 and 0.527 MPa, and the stress
increases compared with that before the frost heaving. The horizontal
displacement of the surrounding rock is -0.36 mm, and the vertical displacement
varies from -9.59 to -8.41 mm. The states of the surrounding rock in terms of
horizontal contraction and arch settlement are 0.36 and 1.18 mm, respectively.
PENG Xiaoli
,
WANG Haijuan
,
YANG Fengchun
,
JIANG Haibo
,
LI Changchang
. Analysis of SurroundingRock
FrostHeaving Characteristics of Diversion Tunnel in Cold Region: a Case Study on Diversion Tunnel Project of Bulunkou Hydropower Station in Xinjiang[J]. Tunnel Construction, 2021
, 41(2)
: 232
-239
.
DOI: 10.3973/j.issn.2096-4498.2021.02.009
