To study the stability of the surrounding rock of nonequalsection crossed caverns, stress concentration phenomena at the
intersection are theoretically deduced. Failure laws of the surrounding rock at
the triangle area of crossed caverns with various diameter differences and
crossed angles are analyzed, and the stress variation law of the surrounding
rock is obtained. Comparisons and contrasts are made between the theoretical
calculation and numerical simulation results of a civil defense enlargement
project in Guiyang, and the results show the following. (1) The stress
concentration coefficient K of the surrounding rocks distributed on the side of the cavern with a large
section diameter. (2) With an increase in the crossed angle (from 30° to 90°), the vertical stress of the
surrounding rock in the triangle area decreases, and the construction condition
is the safest when the caverns vertically intersect. (3) When the hole diameter
difference is two, three, and four times, the maximum value of K in the surrounding rock at the crossed
top is 3.83, 3.60, and 3.21, respectively, indicating that the possibility of
failure in this part of the actual project is the highest. (4) The vertical stress
of the surrounding rock in the triangle area shows an obvious bias distribution
and presents a curved triangle distribution shape.
LIU Ning
,
HUANG Yixiong
,
CAI Wei
,
CHEN Kun
. Theoretical Analysis of Stress Concentration
Distribution of Surrounding Rock in Triangle Area of NonEqualSection Crossed Caverns[J]. Tunnel Construction, 2021
, 41(5)
: 781
-788
.
DOI: 10.3973/j.issn.2096-4498.2021.05.011
