MINI BORE PILE

Drilling Work

• Rig needs to be positioned properly to avoid misalignment.

• Use the rotary wash boring method, where:
• Drill bits attached to the bottom of a casing rotate to penetrate the ground.
• Water is used as the drilling fluid to flush out soil from inside the casing through fluid pressure.

• The drilling system includes:
• Casing is installed to support the borehole walls during the drilling process.
• Circulated drilling slurry is pumped into the borehole to assist in soil removal and maintain wall stability.
• Slurry overflow is collected and carried to allow for the settlement of soil cuttings.
• The settled slurry is then transferred to a storage pit for further sedimentation.
• Clean drilling water is subsequently recirculated back into the drilling pit, creating a closed-loop system for efficient and sustainable drilling operations.

Hole Cleaning after Drilling

• Once the final depth is achieved:
• Flush the borehole with clean water to remove remaining loose debris, slurry, and fines.
• Ensure the borehole is completely clean to improve grout bonding and maintain hole stability for the next steps.

Rebar Cage Installation

• Rebar is assembled by segments into a single complete unit to form a steel cage.
• The cage is lowered slowly and carefully to prevent any damage to the borehole walls.
• The steel cages can be connected until they reach the full depth of the borehole.

Concrete Installation

• The tremie pipe is installed until it reaches the bottom of the borehole. A funnel is attached to the top of the tremie pipe.
• Once the tremie pipe is in place, a final depth measurement is conducted to check for any risk of borehole collapse.
• Concreting begins by pouring concrete into the tremie pipe.
• This process must proceed without delay to prevent the concrete from setting inside the pipe.
• The length of the tremie pipe may be reduced during the pouring process, provided that the discharge end remains submerged at least two meters into the fresh concrete.