January 19, 2024
Introduction to TRD
TRD (Trench cutting Re-mixing Deep wall method), a continuous wall construction method under equal thickness cement soil, developed by Japan's Kobe Steel in 1993, which uses a saw chain cutting box to continuously construct continuous walls under equal thickness cement soil Construction Technology.
The maximum construction depth in general sandy soil layers has reached 56.7m, and the wall thickness is 550mm~850mm. It is also suitable for various types of strata such as pebbles, gravels, and rocks.
TRD is different from the current column-type continuous wall construction method under cement soil formed by traditional single-axis or multi-axis spiral drilling machines. TRD first inserts a chain saw-type cutting tool into the foundation, digs to the designed depth of the wall, then injects a curing agent, mixes it with the in-situ soil, and continues to horizontally dig and stir, and advances horizontally to build a high-quality cement mixing continuous wall.
Features of TRD
(1) The construction depth is large; the maximum depth can reach 60m.
(2) It is suitable for a wide range of strata and has good excavation performance in hard strata (hard soil, sandy gravel, soft rock, etc.)
(3) The finished wall has good quality, in the depth direction of the wall, it can ensure uniform cement soil quality, improved strength, small discreteness, and good water interception performance.
(4) High safety, the equipment height is only 10.1m, low center of gravity, good stability, suitable for places with height restrictions.
(5) Continuous wall with fewer joints and equal thickness of the wall, H-shaped steel can be set at the optimal spacing.
Principle of TRD
The chain saw cutting box is driven by the hydraulic motor of the power box, and the sections are connected to drill to a predetermined depth, and the horizontal excavation is advanced. At the same time, solidifying liquid is injected into the bottom of the cutting box to forcibly mix and stir with the in-situ soil, and the formed cement soil mixing wall of equal thickness can also be inserted into the profile steel to increase the stiffness and strength of the mixing wall.
This construction method changes the mixing method of cement-soil mixing wall from the traditional horizontal layered mixing of vertical axis auger drill rod to the vertical overall mixing of horizontal axis saw chain cutting box along the depth of the wall.