To test the reliability of the gridsteel
frame applied in primary support of loess tunnel of the heavyhaul railway, a 1∶1 model test of fullring gridsteel frameconcrete structure is conducted,
the deformation convergence of primary support, surrounding rock pressure, and
mechanical property test of gridsteel frame and
shotcrete are analyzed, and statistical analysis of deformation convergence
data of primary support based on big data is studied. The study results show
the following: (1) The fullring gridsteel frameconcrete structure has a high
bearing capacity and large deformation coordination capacity. The H180 gridsteel frameconcrete structure can bear the
loess weight equivalent of the loess stratum with a depth of 32.56 m under the
limit state. (2) The gridsteel frame can be applied to
a largespan loess tunnel with Grade Ⅳ and Ⅴ surrounding rocks, which ensures the
stability of the surrounding rock and the safety of the primary support
structure. (3) The gridsteel frame is used in the
primary support of a largespan loess tunnel, and the
crown settlement and horizontal convergence are well controlled, which are
generally within the control values of excavation reserved deformation.
PI Sheng
.
Application of Grid Steel Frame to Primary Support for
Loess Tunnel on
HaolebaojiJi′an Railway
[J]. Tunnel Construction, 2021
, 41(4)
: 604
-612
.
DOI: 10.3973/j.issn.2096-4498.2021.04.010
