There are several challenges in the longline
matching prefabrication and assembly process of multicabin utility tunnel
segments with large crosssections. These challenges
include the prefabrication of end segments, internal mold design and separation
technology of the large crosssection multicabin
utility tunnel segments, positioning accuracy control of the reserved holes and
embedded parts in the tunnels, and alignment control and rectifying technology
of the segment under the condition of a large longitudinal installation slope.
To address these issues, the characteristics and key points of this technology
are analyzed and studied in detail based on a utility tunnel project of Meishan
Road, Ring East Sea area, Xiamen. Through a field application test and
engineering practice, the following corresponding technical schemes are
proposed. (1) The technology of binding and integral hoisting is used in the
end segment, and a hollow rubber plug and rubber strip are developed for
positioning the exposed reinforcement and steelplate
waterstop. (2) The adjacent tunnel segments are separated using hydraulic push
technology. Moreover, to reduce the friction resistance of hydraulic jacking, a
straw or thin fiber board is used to separate the tunnel segments from the
concrete mould. (3) The split joint structure of the formwork is vertical, and
a hydraulic drive system is used to control the automatic movement and the
opening and closing of the side panel of the internal mold. (4) The positioning
hole is established in the corresponding position of the formwork, and the
quality of the embedded technology is improved by studying and fabricating the
silica gel rod and rubber parts. (5) By measuring the central axis and
horizontal line marked in the tunnel segment, the control of the tunnel segment
alignment is realized; in outoftolerance cases, a singleside support pad
of epoxy resin is used for alignment adjustment. Under the working condition of
a large longitudinal slope, a custommade variablefrequency door machine with threedirectional
fine tuning is used to assemble the segment. Results indicate that the
technical scheme yields good results and economic benefits in practical
applications. Moreover, the proposed scheme is successfully applied to a
utility tunnel project of Xiang′an East Road in Xiamen.
CAI Qingcheng
.
Research and Application of Key Technologies for Longline
Matching Prefabrication
and Assembly of Utility Tunnel Segments
[J]. Tunnel Construction, 2020
, 40(10)
: 1488
-1597
.
DOI: 10.3973/j.issn.2096-4498.2020.10.013
