Long-distance pipe jacking through complex geological strata faces the
challenges of difficult jacking, difficult mud wall formation, and excessive
ground disturbance. To address these issues, a case study is conducted on a
long-distance rectangular pipe jacking project crossing
underneath Beijing-Hangzhou Grand Canal, and the
mechanical behavior of long-distance pipe jacking and
the influence of pipe jacking on surrounding environment are systematically
examined. Based on the friction coefficient of slurry obtained from field test,
the peripheral friction resistance of the pipe is calculated using soil column
theory, thus obtaining the pipe jacking force at different jacking distances.
The varying process of jacking force, speed, and parameters (slurry feeding
pressure, grouting pressure, and slurry chamber pressure) in response to long-distance pipe jacking underneath river is analyzed, and the surface
settlement pattern under double-line pipe jacking
condition is summarized. Some conclusions are drawn as follows: (1) The pipe
jacking force calculated by slurry lubrication theory is reduced by
approximately 40%, which is closer to actual values. The slurry lubrication
theory improves the calculation accuracy by adjusting friction coefficient. (2)
When jacking in different strata, the difference in the properties of the
strata and the large pipe jacking deflection angle lead to significant change
in jacking force. (3) Under high water pressure condition, controlling the
grouting pressure according to burial depth and water pressure effectively
guarantees stable working face and surrounding soil, minimizes ground
disturbance, thus avoiding excessive vertical surface displacement and water
gushing disaster.
WANG Zhiqiang
,
WANG Jinli
,
FAN Dongdong
,
LIU Tianshuang
,
TAN Yong
.
Parameters Analysis of Long-Distance Rectangular Pipe Jacking Underneath Beijing-Hangzhou
Grand Canal
[J]. Tunnel Construction, 2024
, 44(S2)
: 159
-167
.
DOI: 10.3973/j.issn.2096-4498.2024.S2.017
