How to Structural Design a Building/House Step by Step Part-4 (Column Design)

As per our last article How to Structural Design a Building/House Step by Step Part-1, 2 & 3. In this article, we design slab load, slab depth, slab steel design, Slab beam design. Now in this article, we calculated a column design.

Column Design

Below Steps Column Design.

1. Column Size.

2. Column Min Steel Design.

3. Column Ring Size.

Column Size

Pu = (0.4 x fck x Ac) + (0.67 x fy x Asc)

Pu = Axial Load Kn

Ag = Gross Area of Column

fck = Strength Concrete

Ac = Ag – Asc

Asc = Area Steel Concrete

Minum Size of column 230 mm 

Column Min Steel Design

Assume 2% Steel Provided.

Asc = 0.02 Ag

Asc = 0.02 Gross Area of Column | Sp-16 ,P-229

Column Ring Size

Dia of Internal Ties | IS 456-2000, P-49

1. (1/4) x dia of a larger bar

2. 6 mm

Provide a larger to two values.

Pitch of Internal Ties | IS 456-2000, P-49

1. Least Internal Dimension

2. 16 x Dia. of Smaller Bar

3. 300 mm

Provide a smaller of three values.

Column Size Example

Load Calculation 

1. SlabWeight of Slab = (62.94 /2) + (180.97/2) = 121.95 kn.

2. Beam End Point weight Along lx = 13.54 kn

Weight of Beam Along Lx = (0.230 x 0.460 x 25) x 3.2 = 8.464 kn.m 

Along Lx Vu = (8.464 x 3.2) /2 = 13.54 kn

3. Beam End Point weight Along ly = 111.94 kn

Weight of Beam Along Ly = (0.230 x 0.460 x 25) x 9.2 = 24.334 kn.m 

Along Ly Vu = (24.334  x 9.2) /2 = 111.94 kn

4. Total load Calculation = 247.435 kn

Column Size

Pu = (0.4 x fck x Ac) + (0.67 x fy x Asc)

Pu = 247.435 kn

fck = 20 N/mm²

fy = 415 N/mm²

Ac = 0.98 Ag

Pu = (0.4 x 20 x 0.98 Ag) + (0.67 x 415 x 0.02Ag )

247.435 x 10³ = 13.401 Ag

Ag = √ 18496 mm² = 136 mm ≅ 230 mm Min mum 

Column Min Steel Design

Asc = 0.02 Ag

Asc = 0.02 x 230²

Asc = 1058 mm²

Provide 4 Nos. 20 mm dia | SP 16, P. 229

Column Ring Size

Dia of Internal Ties| IS 456-2000, P 49

1. (1/4) x dia of a larger bar

= (1/4) x 20  = 5mm

2. 6 mm

Provided larger 6 mm Ø lateral ties

But we, Provided 8 mm Ø lateral ties

Pitch of Internal Ties | IS 456-2000, P-49

1. Least Internal Dimension =

Least Internal Dimension  = 230mm

2. 16 x Dia. of Smaller Bar

16 x 20 = 320 mm

3. 300 mm

Provide a smaller of three values.

Provide pitch = 230 mm c/c

Provided, 8 mm Ø lateral ties at 230 mm c/c

Column

How to Structural Design a Building/House Step by Step

How to Structural Design a Building/House Step by Step – 4 Download Excel Sheet

Also, read: How to Structural Design a Building/House Step by Step Part-1 (One Way Simply Support Slab)

Also, read: How to Structural Design a Building/House Step by Step Part-2 (Two Way Simply Support Slab)

Also, read: How to Structural Design a Building/House Step by Step Part-3 (Slab Beam Design)