Project Summary

• Project Details:

  • Tunnel Length: 3053.142 meters (from DK58+801.754 to DK61+854.896).

  • Shafts: 1 airport working shaft and 4 access tunnels.

  • Equipment: Two 9-meter diameter CRCHI Slurry-Shield TBM

  • Tunnel Dimensions:

    • Left Line: 436.5 + 2598.3 meters.

    • Right Line: 436.3 + 2597.2 meters.

  • Tunnel Shape: "V" shaped slope with a cover depth ranging from 12.11 meters to 51.00 meters.

  • Critical Infrastructure: The shield tunnels pass beneath airport runways, the existing apron, the southern apron, and the satellite terminal.

Construction Challenges

• Soil Condition and tunnel shape

  • Soil Conditions: Tunnelling through full-section grey silty clay interbedded with silty clay and sand layers.

  • Tunnel Shape: The tunnel has a "V"-shaped slope with cover depths ranging from 12.11 meters to 51.00 meters.

  • Sandy Soil Layer: The shield machine encounters a highly mobile sandy layer in the middle section, which is rich in pressurized water.

  • Challenge: Adjusting the tunnelling parameters to accommodate the strong fluidity of the soil and its water content.

• Critical Infrastructure

  • Tunneling beneath:

    • Airport flight zone runways,

    • Satellite terminal,

    • High-mast light tower zone,

    • S1-S4 subway tunnels at Pudong Airport,

    • Overhead pipelines.

• Operation Difficulties

  • Issues with excessive thrust during tunnelling, resulting in difficulty resuming operation after stoppage. In some cases, the machine could not restart even after a thrust alarm was triggered.