Large mud and water gushing
and soft rock deformation often occur in-tunnel
sections with poor geology. Therefore, an L-shaped
ground directional drilling and grouting with an entire hole length of over 500
m assisted by in-tunnel advance grouting is proposed
for the construction of the Xianglushan tunnel of the Central Yunnan water-conveyance project. The specific design scheme of the proposed
method is determined. First, the on-site geological
survey results reveal the technical difficulties of the unfavorable geological
sections of the Xianglushan tunnel. The construction process and grouting
technology of the L-shaped directional drilling
grouting are explained. Second, a ground reinforcement scheme for L-shaped ground advance grouting is designed to improve the stratum
stability. Finally, the on-site grouting effect is
illustrated by tunnel face revelation, grouting results, and magnetotelluric
analysis. The results show that the Z1 + Z2 + Z4 drilling field design is the
optimal ground advance grouting scheme, and the L-shaped
directional drilling grouting assisted with advance in-tunnel
grouting technology can cover the grouting area in the blind area, realizing
advance reinforcement.
ZHAO Lipeng
,
LI Jian
,
LEI Xiaotian
,
GUO Yaxin
,
WANG Tingchao
,
TAO Zhigang
. L-Shaped Ground Advance Grouting Scheme in Bad Geological Section of Xianglushan Tunnel[J]. Tunnel Construction, 2024
, 44(6)
: 1294
-1304
.
DOI: 10.3973/j.issn.2096-4498.2024.06.016
