Aiming at the problem of
excessive uplift of segment in full-section
stable surrounding rock strata, a new type of synchronous two-component grout is developed and applied to a section of Nanjing
metro line 6 through the combination of laboratory test and field test, which
greatly reduces the uplift of segment and improves the quality of segment
assembly. The single-liquid hard grout used in the
field is used as liquid A, and the new coagulant is used as liquid B. The
influence of liquid B on the properties of liquid A is determined by laboratory
test. According to the requirements of slurry gel time, fluidity, compressive
strength, and combined with the actual situation on site, the ratio of new
synchronous two-component-liquid
grout is determined. The grouting effect of the new synchronous two-component-liquid grout is verified by field
test. The results show: (1) The gel time of the new synchronous two-component grout can be shortened to 10-30
minutes by mixing 1 %-2 % of the total mass of liquid A
with liquid B. The slurry has good pumping performance and high early strength.
(2) The fluidity of the new synchronous two-component
grout can not be lost within 10 min after injection, and with good pumping
perforrnance and not easy to block the pipe. (3) Monitoring data show that the
new synchronous two-component grout has excellent field
grouting effect. Compared with the single hard grout, the overall uplift of the
segment ring is reduced by 50%, the maximum horizontal deviation of the segment
ring is reduced by 57%, the number of leakage points of the segment ring is
reduced by 50%, and the maximum surface settlement is reduced by 74.3%.
WANG Gui, YI Binbin, LI Fudong, ZHONG Xiaochun, JIAN Yongzhou, ZHU Cheng, WU Ronghua
. Synchronous Two-component Grout Development and Backfill Grouting Effect of EPB Shield[J]. Tunnel Construction, 2024
, 44(S1)
: 257
-264
.
DOI: 10.3973/j.issn.2096-4498.2024.S1.028
