Reinforcement detailing of Columns from ETABS output

AIM -

• To provide details for longitudinal reinforcements for two columns from base to terrace.
• To sketch column cross section and elevation details.
• To show shear reinforcement and lapping details as per IS 13920 2016 clause 8.1

PROCEDURE -

1. ETABS> Check model and Run Analysis -

2. Design> Frame Design Preference for IS456:2000 -

3. Design> Design Load Combinations -

4. Design> Start Design/check -

5. Design> Display Design info> Longitudinal reinforcement

6. Design> Display Design info> Shear reinforcement

7. Design of Given Columns -

1. COLUMN 3A

• Size of column- 450X650mm
• Maximum Ast for column is 7027
• provide 16 bars of 25mm as shown.

• Provide T10 @ 100mmc/c over a length of 650mm from the face of the joint towards mid height of column and the shear reinforcement provided as per special confining reinforcement provision of clause 8.1 of IS 13920-2016.
• Provide 150c/c for rest.

b. COLUMN 3B

• Size of column- 450X650mm
• Maximum Ast for column is 4228
• provide 16 bars of 25mm as shown.

• Provide T10 @ 100mmc/c over a length of 650mm from the face of the joint towards mid height of column and the shear reinforcement provided as per special confining reinforcement provision of clause 8.1 of IS 13920-2016.
• Provide 150c/c for rest.

8. Design clause 8.1 of IS 13920-

A) Confining reinforcement length should be atleast:

• Larger lateral dimension of the member 450X650 mm - 650mm
• 1/6th of clear span (3450/6= 575mm)
• 450mm

B) Maximum spacing of confinement should be:

• 1/4th of minimum lateral dimension (450X650) 450/4= 112.5mm
• 6 times smallest longitudinal rebar 25mm X 6 = 150mm
• 100mm

Minimum of 112.5mm, 150mm and 100mm to be taken, therefore spacing of shear link = 100mm

C) Ash Minimum special confining reinforcement should be maximum of A) and B) :

Hence Ash = 663(mm)^2/m.

Requirement minimum special confining reinforcement at column joint-

Provided shear reinforcement at joint: 2 legged T10 @ 100mmc/c

CONCLUSION -

The detailing of columns 3A and 3B are done using ETABS and elevations are drafted according to clause 8.1 IS 13920- 2016