Technology and method

TGC method

What is the TGC method?

An abbreviation for Tachibana Gel Control, it is a two-liquid high-viscosity plastic filler that easily adjusts the gel time and gel strength (shear strength) by changing the mixing ratio of the two liquids (A and B). can be controlled to
In addition, this filler is a plastic filler that has a proven track record in many applications, such as preventing over-excavation collapse during construction of sharp curves in over-excavation sections, preventing subsidence of the ground surface, and filling chambers before the start of the shield.


  1. Both liquids A and B have excellent fluidity and can be pumped over long distances.
  2. After mixing, the viscosity gradually increases and becomes homogel-like in a few minutes.
  3. It is a filler with excellent long-term stability without material separation or property change after mixing.
  4. Excellent underwater separation resistance
  5. Excellent filling properties due to plasticity
  6. Since this filler is not easily affected by metal ions and chloride ions, it can be used in cement-based ground improvement sections, chemical injection sections, and ground where seawater (salt) is contained in the groundwater. be
  7. By using the same material and equipment as the shield backfilling injection method (clean back method), it is possible to create and fill without adding equipment.

Purpose of use (shield construction)

  1. Filling material for overdrilling (steep curve construction)
  2. Subsidence suppression material (low overburden)
  3. Filling material in the chamber (before starting the shield machine)
  4. Excavation Additive (Mud Pressure Excavation Additive)
  5. Auxiliary materials for pumping (mud pressure type earth and sand pumping method)
  6. Soil pressure retention material (prevention of ground subsidence, stabilizing cutting face)
  7. Friction reducing material around the machine body (measures to prevent tightening)
  8. Vibration reduction material for the machine circumference (measures to prevent ground shock absorption)