Civil Engineering Reference
In-Depth Information
auxiliary equipment required to enable the boring process to progress
properly was assembled on or in these trailers. The first two trailers con-
sisted of a welded frame made of steel sections. They were coupled hori-
zontally by means of a differential to the TBM and to each other. These
hinged couplings were necessary to guarantee the required flexibility when
making horizontal and vertical bends. The dead load was transferred verti-
cally by sets of wheels on the concrete lining. In order to transfer this load
on the concrete as optimally as possible, the sets of wheels were located
under the trailers in a radial tunnel direction. In addition, the design of a
bogie frame made it possible for the load to be equally distributed over sev-
eral wheels.The treads of the wheels were made of a synthetic material and
the profile of the treads followed the radius of the inner diameter of the tun-
nel. From previous experiences with tunnel boring machines, it was shown
that trailers in some cases had the tendency to creep up against the lining
during the progress of the boring process. In order to prevent this, all the
trailers were fitted with bogies adjustable in the longitudinal direction.
Logistical freedom and parallel works
Space had to be available behind the TBM in the completed tunnel section
for amongst other things, the delivery of tunnel ring segments by train,
the delivery of pipes and grout mortar, and the arrival and departure of per-
sonnel during the boring process. In addition, immediately after the TBM
had passed through, the backfill on which the roadway would be situated
and the cable gallery incorporated in it, was constructed.
In order to prevent the complexity of the logistical process from causing
problems, the trailers behind the first two were designed as a number of
platform carriages with hinged couplings. The platform of these carriages
was at the same level as that of the upper decks of the first two trailers. The
use of sufficient numbers and lengths of all the carriages resulted in a cer-
tain degree of logistical freedom which made it possible to carry out several
tasks at the same time without them obstructing each other.
Fig. 10.10
Laying the cable
gallery and backfill
Search WWH ::
Custom Search