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In 1987 the Robbins-Markham Joint Venture (RMJV) was awarded a
£15m contract to supply two machines for the Marine Rail tunnels driving some
22km towards France.
Bennett Associates was awarded a contract by RMJV to design and
produce detail manufacturing drawings for the 235m long back-up system to the
Tunnel Boring Machine (TBM) and a contract from the Robbins Company, USA to
carry out a full Finite Element Stress Analysis of the Tunnel Borning Machine
which they were designing.
Design of the TBM back-up system
The back-up system consisting of thirteen articulated gantries,
running on temporary rails, performs the following functions:
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Offloads, transports and places 1.5m wide
precast concrete segments in position to form to form the tunnelling lining. The
45 ton segment ring in nine pieces has to be built in 15 minutes. |
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Transport muck from the cutterhead on conveyors at a peak
rate of 1,500 and normal rate of 1000 tonnes per hour. |
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Supports the TBM with all services paid out continuously as
the machine advances. The power supply is 2,300kw at 11,000 volt, clean water in
by 4" dia hose reel, dirty water out by 6" diahose reel, inrush water out 12"
dia x 2 telescopic pipes, fresh air in by 2m dia flexible duct plus radio
telephone and computer data links. |
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Performs and supports a high pressure grouting system,
filling voids between pre-cast lining and the ground. |
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