Tunnels
constructed by mining methods always have many problems such as voids behind
the lining structure and insufficient thickness and strength of secondary
lining. Accordingly, a novel prefabricated segment for the tunnel arch is
proposed. Based on a doubletrack tunnel with a speed of 350
km/h, a series of design parameters of prefabricated tunnel lining at tunnel
arch are studied using numerical calculation and analysis methods. Main
conclusions are drawn as follows: (1) The integral prefabrication form of arch
fabricated lining in the circumferential direction is proposed. Considering the
theoretical calculation results, traffic safety analysis, transportation and
assembly capacity of mechanical equipment, bearing capacity of arch lining,
etc., the structural dimensions and reinforcement design parameters of arch
segment circumferential chord length of 8.6 m, longitudinal width of 2 m, and
lining thickness of 50 cm are determined. (2) The arch preproduction tube slice is connected with each other by bolts, which
also be connected with castinplace
sidewall by Ltype tenon joints. Meanwhile, the
dimensions design parameters of the tenon joints are proposed. (3) To ensure
the smooth installation of arch segments, the construction error should be
considered for the tenon joint of castinsitu sidewall, and an installation space shall be reserved between
the arch segment and the primary support. After the segment is installed, the
space between surrounding rock and segment shall be filled and compacted by
longitudinal grouting at the back. The prefabricated lining at tunnel arch has been successfully applied to the Hujiagou
tunnel in Chongqing, China, and the overall implementation effect is good.
WANG Song, XIE Yunlai, QING Weichen, YANG Changyu, WANG Jianhong, YANG Yi
. Design of Prefabricated Lining Structure at Tunnel
Arch Constructed with Mining Method[J]. Tunnel Construction, 2022
, 42(S1)
: 360
-368
.
DOI: 10.3973/j.issn.2096-4498.2022.S1.041
