This is an easy process of pile reinforcement calculation.

I follow this process every time whenever I need to know the required steel quantity for piles of my building projects.

Following this process, you’ll be able to calculate the pile reinforcement easily.

Let’s first know about…

## What A Pile Is?

A pile is basically a column which is built underground.

Typically it’s a long cylinder of a strong material such as concrete or steel that is built or pushed into the ground to support structures built on top of it.

To know more about piles, read the post, Pile Foundations: Everything You Need To Know As A Construction Professional.

Piles can be made of steel or RCC.

Here we’ll talk about the reinforcement calculation process of RCC piles.

So, let’s learn the…

## Process Of Pile Reinforcement Calculation

Follow the steps below…

### Step-1: Count The Number Of Piles

**First**, open the PILE LAYOUT PLAN from your structural drawing book.

That looks something like:

**Now**, Count the numbers of similar piles.

In our example drawing:

- P1 = 8 Nos

- P2 = 4 Nos

- P3 = 3 Nos

- P4 = 4 Nos

With that, go to…

### Step-2: Get The Quantity Of Main Steel

You’ll have a separate drawing in your structural drawing book showing the detailing of pile reinforcements. That looks like:

This is an example of the reinforcement detailing of **P1**.

**First**, analyze the drawing carefully.

In our example drawing, we have:

6 numbers of 20mmØ bar in section 1-1.

6 numbers of 16mmØ bar in section 2-2.

**Next**, get the length of bars.

The length of a 20mmØ bar is 39 feet (clearly shown in our example drawing).

So, the total length is,

= 6 × 39′

= 234 feet

= **175.50 kilograms** (Unit weight of 20mmØ is 0.75 kg/feet)

** Read More: **How to Calculate the Unit Weight of Steel Bars

The pile also has 16mmØ bars.

The length of a 16mmØ bar is 37 feet (That is also shown in our example drawing).

But there is a lap which is 2′-6″ long.

So the length of the 16mmØ bar is,

= 37′ + 2.5′

= 39.5 feet.

And

The total length is,

= 6 × 39.5′

= 237 feet

= **113.76 kilograms** (Unit weight of 16mmØ is 0.48 kg/feet)

### Step-3: Calculate The Spiral Reinforcement

The PILE REINFORCEMENT DETAILING drawing also shows the spacing and size of the spiral bars.

The formula for calculating the length of a spiral bar is,

= **Number of turns × √{(Circumference of spirals)2 + (spacing of turns)2}**

**First**, Calculate the number of turns

The formula is,

= Length ÷ spacing

The length is 73 feet.

So, the number of turns are,

= 73′ ÷ 8″ [8″ is equal to 0.67′]

= 109 numbers

**Next**, calculate the circumference of the spiral.

And the formula is,

= **ℼd**

d is the diameter of the spiral which is,

= Diameter of the pile – 2 × concrete cover

= 18″ – 2 × 3″

= 12″

So, the circumference of the spiral is,

= 3.14 × 12″ [ℼ = 3.14]

= 3.14 feet.

**Next**, put all these into the formula. That is,

= Number of turns × √{(Circumference of spirals)2 + (spacing of turns)2}

= 109 × √{(3.14′)2 + (8″)2} [note: 8″ = 0.67′]

= 349.96 feet

Say, 350 feet.

That means the length of the spiral bar for our example pile (P1) is 350 feet.

But in the market, we get steel bars not more than 40 feet long.

So, we definitely need to provide laps to join the bars together.

Considering 40 feet long bars, the number of laps will be,

= 350 ÷ 40

= 8.75

Say, 9.

If we provide one foot long laps, we need to add 9 feet more bars for our spiral.

And the total length will be,

= 350 + 9

= 359 feet

**Finally**, calculate the weight of spiral bars.

The weight of bars,

= length of bars × unit weight

As we have 10mmØ bars for spiral in our example drawing so the unit weight of that is 0.19 kg/feet.

And the weight is,

= 359 × 0.19

= **68.21 kilogram**.

### Step-4: Calculate The Total Steel Quantity For All Piles

In the above three steps, we calculate reinforcement for one pile which is P1.

And the required reinforcement for P1 is, in summary:

- 20mmØ bars – 175.50 kilograms

- 16mmØ bars – 113.76 kilograms

- 10mmØ bars – 68.21 kilogram

But we have, in our example drawing, 8 numbers of P1 pile.

So, the total required steel quantity for all the P1 piles are:

- 20mmØ bars – 176 × 8 = 1408 kilograms

- 16mmØ bars – 114 × 8 = 912 kilograms

- 10mmØ bars – 69 × 8 = 552 kilogram

Now follow the **step-2** and **step-3** to calculate the reinforcement for P2, P3, and P4.

Finally, sum up all the same size bars together.

That’s it.

Easy, right?

**Conclusion**

Pile reinforcement calculation is easy.

First, Count the number of piles.

Next, calculate the quantity of the main reinforcement.

After that, calculate the spiral reinforcement.

And finally, sum up all the reinforcement together.

*Your Turn:*

*This is the process I follow for pile reinforcement calculation.*

Do you know any quick process other than this?

Please share in the comments below…

And If you liked the post, do share your favorite social media channels.

Do you know any quick process other than this?

Please share in the comments below…

And If you liked the post, do share your favorite social media channels.

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