Unformatted text preview: is 2000 to 12000 Joules
(2740 to 8760 ft. lbs.)) is used for tunneling purposes (Giovene 1990). The impact
hammer usually has a chisel tool of self-sharpening design.
Rock Conditions: This system is best suited for fissured, jointed and well layered of foliated rock mass. Massive rock conditions usually slow down the progress but strong rocks
with pronounced joints and bedding planes and weak bonding; favors this technique.
10.10 EXCAVATION PROCEDURE AND CYCLE OF OPERATIONS5
This technique is suitable for the tunnels exceeding cross section 30 m2 but in smaller
tunnel than this will pose the operational problems due to the restricted space. In narrow tunnels (width less than 8 m); only one set of ‘Hammer and Excavator’ can work
at the face. The work is usually divided into following unit operations:
● Excavation by hammer
Muck handling by the excavator
Scaling and handling the scaled muck
Supporting the tunnel using type of support as applicable. If the tunnel is of mo...
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- Spring '14
- Francis Group, Taylor & Francis Group, Excavator, roadheaders