To accurately predict the longitudinal deformation of
an existing shield tunnel caused by newlybuilt overcrossing tunnel, the
Kerr foundation model is introduced that can more reasonably simulate the
tunnelsoil interaction and the existing tunnel is
simplified as the EulerBernoulli beam on the Kerr
foundation. Then, based on the Mindlin solution, the additional stress
generated on the axis of the existing tunnel by the newlybuilt tunnel excavation is determined. Furthermore, based on the
finite difference method, the solution of longitudinal deformation of the
existing shield tunnel induced by the overcrossing of the newlybuilt tunnel is obtained. Finally, three engineering cases are used
to verify the effectiveness of the proposed method, and some parameters are
analyzed and discussed. The results show that the proposed method can predict
the longitudinal deformation of the existing shield tunnel induced by the new
tunnel overcrossing more accurately than predicted by the Winkler and Pasternak
foundation models. The results of the analytical parameters reveal that with
the increase in the newlybuilt tunnel′s diameter, the uplift value and influence range of the existing
tunnel increase simultaneously, while the increase in the clearance slightly
reduces the uplift value of the existing tunnel, but does not affect the
influence range of the existing tunnel. Thus, deformation monitoring and safety
measures should be adopted for the existing tunnels when a newlybuilt tunnel is crossing above with a large crosssection or small clearance.
GAO Kun
,
SU Xiaofeng
,
ZHANG Zhiwei
,
LIANG Rongzhu
,
LI Zhongchao
,
GUO Yang
,
YUE Tengsheng
. Longitudinal Uplift Analysis of Existing Shield Tunnel
Induced by New Overcrossing Tunnel[J]. Tunnel Construction, 2023
, 43(5)
: 770
-778
.
DOI: 10.3973/j.issn.2096-4498.2023.05.004
