Reinforcement detailing of Columns from ETABS output

Aim:

To run and analyze and design the RCC moment-resisting frames of the given ETABS file and to provide details of longitudinal reinforcement for the two columns (3A & 3B) from foundation level to terrace level.

• Provide details of longitudinal reinforcement for the two columns, from foundation to terrace level. Sketch the column cross-sectional & elevation details or draft it using AutoCAD software.
• Show shear reinforcement & lapping details as per special confining reinforcement provision of clause 8.1 of IS 13920 - 2016.

Procedure:

• Open ETABS software of given etabs file.
• Check the model and run the analysis.
• There should be no errors and warnings.
• 
• Go to frame design performance and check it.
• 
• Go to Design combination
• 
• Click on start design and check.
• 
• Now we need to draft the column reinforcement details on AutoCAD.
• The reinforcement details for column 3A.
• 
• Hence, the maximum longitudinal reinforcement required is 7027
• Hence provide 10 no.s of 32mm dia bars
• Now, for the shear reinforcement, the maximum reinforcement area required is 720 sq.mm.
• 
• Hence provide 8mm dia bars @150mm c/c s
• 
• As per clause 8.1 of IS13920-2016, The special confining reinforcement is calculated
• a)Confining length Lo should be at least.

1. Larger dimension of the frame member (650mm)
2. 1/6th of clear span (575mm)
3. 450mm

• As per clause 8.1 section, b) the maximum spacing of confining reinforcement shall be

1. 1/4th of minimum member dimension (112.5mm)
2. 6 times of smallest longitudinal rebar (192mm)
3. 100mm.

• So minimum shear link spacing maintained 100mm.
• Then provide an 8mm dia bar of spacing 100mm c/c of top and bottom of the column.
• 
• The reinforcement details for column 3B.
• 
• Hence, the maximum longitudinal reinforcement required is 5046
• Hence provide 4 no.s of 32mm dia bars and 6 no.s of 25mm dia
• Now, for the shear reinforcement, the maximum reinforcement area required is 720sq.mm.
• 
• Hence provide 8mm dia bars @150mm c/c s
• 
• • As per clause 8.1 of IS13920-2016, The special confining reinforcement is calculated
  • a)Confining length Lo should be at least.
  1. Larger dimension of the frame member (650mm)
  2. 1/6th of clear span (575mm)
  3. 450mm
  • As per clause 8.1 section, b) the maximum spacing of confining reinforcement shall be
  1. 1/4th of minimum member dimension (112.5mm)
  2. 6 times of smallest longitudinal rebar (192mm)
  3. 100mm.
  • So minimum shear link spacing maintained 100mm.
  • Then provide an 8mm dia bar of spacing 100mm c/c of top and bottom of the column.
• 

Result:

Thus the detailing of two RC columns where done using AutoCAD and special confining reinforcement is verified with respect to IS13920 clause 8.1.