080731 6LYG A1 Particular Tunnelling Specification ... - SCATnow

Lee Tunnel, Contract No. 6LYG/A1
PT – Particular Tunnelling Specification - PT200
f) Quality assurance audit proposals
i) A statement detailing the records that will be kept and supplied to the
Project Manager.
ii) Inspection and test plans for each activity requiring inspection and the
level of that inspection.
g) TBM Detail Plans showing:
i) Cutters, cutter head and overcut
ii) Conditioner generation and injection system
iii) Integrated support pressure control system
iv) Thrust, steering and drive systems, including main bearing
v) Shield articulation details demonstrating compliance with the minimum
radius requirements.
h) Spoil Treatment
i) For EPBM, provide details of type of conditioners to be used, mixing
methods and proposed muck to conditioner ratios, and a description of
the various conditioners used in anticipated ground conditions for the
TBM.
ii) For SPBM, provide details of the slurry treatment plant and operations,
slurry and conditioner materials and additives to be used. This is to
include the number of centrifuges that the Contractor proposes to provide
and the assumptions made in the design of the Separation Plant.
i) Product Data
Provide data sheets for materials to be used for tunnel excavation including
shelf life and handling and storage instructions particularly any polymers shall
be submitted for acceptance by the Project Manager.
j) Risk Assessments for the type of TBM selected and associated tunnelling
method.
The Contractor shall submit a comprehensive and detailed risk assessment
for the above. This shall take into account the following:
i) The strategy for interventions into the cutting head for planned and
unplanned maintenance or monitoring in high water pressures.
ii) The ability to undertake major repairs to the TBM.
iii) The issues associated with transporting spoil within the tunnel and shaft.
iv) The ability to achieve long term production rates.
v) Wear resistance of the cutter head, tooling and other wear parts.
vi) The risk of TBM rolling due to high cutter head torque.
k) Ground Settlement Control
i) The contractor shall submit to the Project manager within 28 days of the
award of Contract, the operation and control features for the TBM to
minimise subsurface and ground level settlement as described in
PT206.2.
ii) A TBM Hazard and Risk Assessment, to be submitted a minimum of 28
days after award of the Contract. The TBM Hazard and Risk Assessment
is to include the following:
Thames Water Utilities Limited August 2008
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