# Bar Bending Schedule Of Pile Foundation

Pile foundations should be applied based on the following conditions where deep foundation is necessary.

• The Soil is extremely compressible and not able to support the load. Therefore, it is necessary to attain the hard strata
• The structure undergoes horizontal forces which happen in skyscrapers (wind force)
• Elevating force with surplus water table.
• Existence of Expansive soils where soil frequently swells and shrinks.

Pile Foundation Diagram - Standard pile foundation diagram comprises of the following:

• Structure
• Pile Cap (supported by number of piles)

Bar Bending Schedule for Pile Foundation Reinforcement - The pile cap part stands for a simple rectangular concrete slab that can be calculated with rectangular volume formula (L X B X h)

• The pile column should be attached with inner spacer ring and exterior helical or spiral ring.
• The Anchorage bar is bent into the column at bottom
• The Development length is arranged outside at top of the column (that is inserted into Pile Cap later on)

The Pile contains three sections:

1. Vertical bar
2. Inner Spacer Ring
3. Outer Helical Ring

Step 1 – Measure the Length of Vertical Bar

Cutting length of vertical bar = Pile anchorage length Bottom + Height of Pile + Development Length Upper + Lap Length(50d) – Clear Cover bottom

Formula Explanation: From the BBS for Column post, it is found that the rod will be 12.2 m or 39 Feet length.

Therefore, it is necessary to lap supplementary bars to maintain 20 m height. For this reason, 40d lap length should be added. The bars should be secured at middle, not at upper or bottom where extreme stress exists.

The following formula is used for calculation :-

Cutting length of vertical bar = Pile anchorage length Bottom + Height of Pile + Development Length Upper + Lap Length(50d) – Clear Cover bottom

= 300mm + 20000 mm + 40d + 50d – 75mm = 300mm + 20000 mm + (40X12) + (50X12) -75mm
= 21.30 m or 21305mm

Total Length of Vertical bar = 21.30 m

To learn other steps, go through the following article civilology.com