- Pathanamthitta, Kerala
- info@mtechc.com
Setting out reference points for cross passage location on the tunnel segments as per the drawings. For setting out survey point total station will be used.
The location of the Probe Holes will be decided by the Tunnel-Engineer/or Geotechnical Expert. In general, these test holes will be drilled in The
Chemical grouting will be used in grouting which comprises of Sodium Silicate and Cement. The grouting criteria are based on the in-site soil conditions and are
Marking of grouting pattern points as per the sketch shown below
Prior removing the centre piece of the entry segment and starting the excavation work, a Segment support will be installed.
After Completion of Cross Passage Fore poling Support i.e., structural steel ring supporting frame.
After installation of top and bottom lintels or Temporary ring, we can start to remove the centre segment part to allow entry for the cross passage works.
The excavation of the cross passages will be carried out wherever it is possible with small excavators, rock breakers like Tata Hitachi TMX-20 & Hilti 1000AVR.
From the face, the muck shall be loaded by TMX-20 and transported into a muck dumper (407 Tipper) stationed inside the tunnel.
Immediately after excavation, Primary lining with sprayed concrete will be applied. The Primary lining and other details shall be followed as per approved drawing.
After completion of first layer of shotcrete, wire mesh shall be installed. To support this wire mesh, nails shall be placed on first layer of shotcrete.
Shotcrete shall be used as per approved drawing. The shotcrete mix ratio shall be followed as per approved mix design.