Φ 11.85m CRCHI EPB TBM

Project Year: 2024

Entrance Seal Design

Project Overview:

Shenjiang Railway SJSG-3 segment: 12.451 km, including shield tunneling and mining construction.
"Leading Pilot" shield machine's first section: 4566.4 meters.

Launch Seal Design:

Composed of rubber curtains and foldable pressure plates for effective sealing.
Critical for smooth tunnel initiation, especially in complex, water-rich strata.
Consequences of Seal Failure:
- Risk of water and sand inflows.
- Potential outcomes: surface collapse, traffic disruption, building damage, shield machine burial, and personal safety hazards.
- Major social and economic impacts, leading to severe financial losses.

Stable pressure is established at the tunnel entrance.
During the sequential opening and closing of the reserved holes in the portal, Jello-Mud is fully extruded without any gas or liquid leakage.
When the ball valve at the observation port of the backfill grouting hole is opened, Jello-Mud is extruded without any gas or liquid leakage.
Jello-Mud exhibited void-filling, sealing, and water proofing capabilities
Contractor was able to save on costs compared to using high-cost tail-seal grease to seal the entrance ring
For more information on how Jello-Mud assisted in lubrication and settlement control in this project, please contact us for more details.

Illustration of Jello-Mud sealing the TBM entrance ring

Site photo indicating no Jello-Mud was stuck on the shield body, a good indicator of its lubrication capability.