The authors investigate the
mechanical behavior of internal soil cohesion and the adhesion between clay
soils and metal cutterheads during mud cake formation. The shear failure modes
of soil samples under two shear methods are analyzed. A self-developed rotational torque test device is used to conduct vane and
plate shear tests on four types of soil: pure illite, pure kaolinite, pure
montmorillonite, and sand-illite mixtures. The findings
are as follows: (1) With increasing normal pressure, both peak and residual
torque increase for vane and plate shear, with peak torque showing a strong
linear correlation with pressure. (2) Compared to pure illite, sand-illite mixtures exhibit higher peak torque and lower residual
torque. (3) For illite, kaolinite, and montmorillonite, peak and residual
torque under both shear methods exhibit significant linear correlations;
montmorillonite yields the highest torque values, followed by illite and then
kaolinite, indicating montmorillonite poses the greatest clogging risk. (4)
Vane and plate shear torque values are linearly correlated. For the same soil,
the slopes of fitted lines for both peak and residual torque are nearly
identical under both test methods. When clogging risk is highest, i.e., when
the consistency index reaches 0.625, shear failure occurs within the soil, and
cohesion is lower than adhesion to the cutterhead.
LIU Xuedan
,
ZHUO Bin
,
FANG Yong
,
DONG Weijie
,
LI Bochang
,
PEI Chengyuan
. Shear Characteristics and
Failure Modes of Clay Soil in Plate and Vane Shear Tests[J]. Tunnel Construction, 2025
, 45(6)
: 1163
-1170
.
DOI: 10.3973/j.issn.2096-4498.2025.06.011
