A case study is conducted on a sludge solidification
project of Bid 3 of a publicprivate partnership project of the
Lianghu tunnel (Nanhu section), and adaptability tests of a lakephase silt solidification agent are conducted to investigate the
composition ratio, dosage, spraying, and stirring process of the solidification
agent, to provide launching conditions for ultralargediameter shields in urban lake island building cofferdams.
Furthermore, the solidification effect of sludge is clarified through light
dynamic penetration tests and thickness tests of the solidification slurry
layer to obtain the optimal amount of curing agent and process. The
experimental research results suggest the following: (1) The curing agent
adaptation and onsite insitu
solidification tests demonstrate that the technology is feasible for lakephase sludge and meets the requirements of construction bearing
capacity and other indicators. (2) A solidified agent with a mass ratio between
cement and industrial waste of 6∶4, solidified
admixture dosage of 1‰, and geopolymer solidified
dosage of 10.5% exhibits a good treatment effect, considering the strength and
uniformity of the solidified soil of the sludge in the Nanhu section. (3) A solidification
process with four stirring and spraying cycles is more conducive to ensuring
the demand for a unit volume of curing agent dosage, reducing slurry waste, and
uniformly strengthening the silt layer. A reasonable amount and solidification
process of silt solidification are proposed, which successfully improves the
solidification strength uniformity of sludge by evaluating the solidification
effect of silt in the experimental field of building an island cofferdam under
different working conditions.
SONG Xiangshuai
,
HE Yuan
,
HAN Xiaoming
,
XU Chao
.
Study on InSitu Solidification of LakePhase Silt in an Island Cofferdam
Construction for Launching a 16m Shield
[J]. Tunnel Construction, 2024
, 44(2)
: 288
-295
.
DOI: 10.3973/j.issn.2096-4498.2024.02.008
