Video summary

Pile Foundation Procedure l Complete Step By Step l Piling Work

Main summary

Key takeaways

Educational

Main ideas / concepts covered

  • Purpose of pile (file) foundation: Used when the ground consists of soft, low load-bearing soils (e.g., clay / black cotton soil) where the required founding stratum (hard rock) is not available within practical depth.

  • Load transfer mechanism:

    • The building’s loads must reach a deep competent layer (hard strata / rock).
    • Concrete piles transfer loads downward through weaker soil and into the hard strata, bypassing the low-capacity soil zone.

  • Overall stepwise workflow: The video presents a complete procedure from: marking pile points → boring → casing/temporary support → lowering reinforcement cage → concreting (including “tremie/creamy” method) → removing casing → pile cap construction → testing (integrity + dynamic load) → plinth/columns above.

Methodology / step-by-step procedure (detailed)

1) Understand why piles are needed

  • Identify that hard rock / competent strata is unavailable at shallow depth (example given: soil thickness up to about 20 m or similar).
  • Recognize that the upper soil is low bearing capacity (e.g., clay / black cotton soil).
  • Decide to use a pile foundation so loads transfer to hard strata at depth.

2) Plan and marking of pile locations (file points)

  • Start from building drawings showing the pile layout:
    • Center line / grid-based layout
    • Cases of single pile or group piles
    • Pile caps arrangement
  • Transfer pile locations from the grid/architect plan to site:
    • Use X and A (X and Y / grid directions) coordinates from the grid.
  • Mark pile points on the ground using a Total Station:
    • Physically set out coordinates at the site.
    • Mark the pile point accurately in the field.

3) Boring / excavation for piles

  • After marking, begin boring with a ring machine (pile boring rig).
  • Concern: boring may disturb the marked position.
  • Mitigation:
    • Establish reference points at 90° directions (X and Y reference).
    • Continuously check pile hole alignment during boring.
    • Ensure the hole remains at the correct location.

4) Prevent collapse of the borehole (casing and bentonite options)

  • Problem: when boring reaches depth, the soil may collapse.
  • The video lists three approaches:
    • Temporary casing: stabilize the bore wall during drilling.
    • Permanent casing: keep casing in place even after concreting.
    • Bentonite slurry / bentonite properties:
      • Use bentonite mixed with water so cavity walls are supported and collapse is minimized.
      • Bentonite forms an expanding layer/lining.

5) Determine and verify depth during boring (“changing”)

  • Confirm the boring has reached required depth using a chain + heavy weight method (“changing”):
    • Drop the weight until it touches the pile base.
    • Measure and confirm the actual depth (examples mentioned: 14 m / 15 m / 15.5 m scenarios).

6) Reinforcement cage (cage lowering)

  • After boring is complete:
    • Proceed to lower/install casing (as per the selected casing strategy).
    • Lower the reinforcement cage into the hole.
  • Use the cut-off level concept:
    • The cut-off level controls where the pile cap and upper works connect.
    • Reinforcement cage positioning is aligned relative to this cut-off.
  • Ensure the cage remains straight during lowering.

7) Concreting method (tremie / “creamy” method described)

  • Concreting using a tremie / creamy pipe approach:
    • Insert the tremie/pipe into the bore.
    • Start concreting from the bottom so the concrete fills properly.
    • Keep the pipe inside the concrete as concreting progresses (lift gradually).
  • Concrete quantity management:
    • Concreting should continue above the cut-off level to account for required trimming/breaking.
  • End step:
    • After concrete is placed to required height/volume, remove the tremie/pipe.
    • Remove temporary casing after concreting is complete.

8) Trimming / breaking to cut-off level and define pile head

  • Extra concrete may be placed above the pile head/anklet (example practice mentioned: ~1 meter approximate concrete) to allow removal of slush/impurities.
  • Break/trim at the cut-off level:
    • Remove the weaker top portion so remaining concrete is sound.

9) Pile cap construction and transition to superstructure

  • Build the pile cap after confirming pile quality.
  • Then proceed to:
    • Plinth level work
    • Columns above (start of the superstructure)

10) Testing after pile concreting (before/for pile cap)

The video emphasizes checking pile quality and capacity via:

  • Integrity test (to detect defects such as):
    • Bulging
    • Cracks
    • Whether concrete is proper
    • Confirm depth/position
    • Ensure pile is correctly aligned/location (mentions “diversion from location”)
  • Dynamic load test (to verify load-carrying capacity against design)
    • Example mentioned: design load might be 500 (units not specified)
    • Purpose: confirm whether the pile can safely carry the required load

Speakers / sources featured

  • Single speaker: An unnamed presenter who introduces himself as a trainer/teacher from “Civil Construct Civil Engineer and Construction Professional Training Institute” and explains the procedure.

  • Source of video content: The presenter’s YouTube video titled: “Pile Foundation Procedure l Complete Step By Step l Piling Work”

Original video