Unformatted text preview: utdown; and this feature enable its use in the changing rock conditions.
Large tunnels and openings can be subdivided and excavation activities can be carried
simultaneously in these sections/divisions.
Low Investment : Compared to the TBM, for the similar size of cross-section; the investment costs for roadheaders amount to be approximately 0.15 (large sections) to 0.3
(small sections). Since they are available on rent basis, as such, they can be used even
for small projects.
Quick and Easy Mobility: Comprehensive assembled equipment and chambers are not
required. Delivery time is usually 3–6 months, and immediate after the delivery they
can be brought into operation.
10.6 IMPORTANT DEVELOPMENTS
Alpine Miner Tunneller AMT 70 has been specially developed for NATM.11 NATM
uses the techniques and equipment that can produce high quality excavations in soft
ground and adverse conditions. This unit has special features to excavate tunnels of
the size 60 m2 or more.
Use of water jet operating at pre...
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- Spring '14
- Francis Group, Taylor & Francis Group, Excavator, roadheaders