Grouting in Tunnel

Jet Grouting (Horizontal): – An efficient and versatile technical solution for tunnelling in different soil, usually with high granulometry, the presence of intense water flow and high hydraulic gradient.

The construction of the Main tunnel and Escape Tunnel through quaternary deposits, consisted of silty-clayey soil with gravels, pebbles, cobbles and occasionally boulders. Horizontal Jet Grouting columns have been used to support the tunnel excavation(first time in India).

It is a mono-fluid system type. The jet Grouting columns 18m long & 600mm dia at the periphery (450mm at face) are executed side by side to form a pre-consolidated arch which follows the external profile of the excavated section.

In this process, the soil is cut, replace and mix in the site Directly with the stabilizer (cement grout) which is injected at very high pressure (400 bar). The jet stream coming out from the nozzle located on a specific ‘monitor’, destroys the natural soil structure & creates a mixing effect between ground and grout.

Machinery used: –

Machinery used: –
1) Casagrande PG – 185
(Specs- •Drilling speed – 400rpm
•Mast length – 23 m
•Stroke length – 18 m)
2) Compact unit (High-pressure pump + Mixing plant TW 4020)
(•Max Pressure – 80MPa)
3) Horizontal Silo – TW silo 50T

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