Reinforcement Detailing of Beams from ETABS output

AIM - Detail design of beams in Etabs 2018.
The ETABS file for a G+4 building is provided. Run the analysis and design the RCC Moment Resisting Frame. The following challenge deals specifically with two continuous beams in the 1st floor.

1) 3 span continuous beam along grid A
2) 7 span continuous beam along grid 3

Address the following issues thereafter.
• Provide details of longitudinal and shear reinforcement for the two continuous beams. Sketch the beam elevation details or draft it using autocad software. A sample of how beam elevation details is prepared in consultancy firms is provided below. Participants can prepare it as per their preference:

• Provide reasons for failure of the middle span along grid A. What are the possible ways this issue can be resolved?

• Calculate value of the maximum shear force in any one of the spans in both the continuous beams, as per clause 6.3.3 (b) in IS 13920 – 2016. Also, confirm these values from shear force demand calculated by ETABS. Please note that if longitudinal reinforcement provided is more than required (as per ETABS results), the shear force demand will vary from what is provided by ETABS.

Procedure -

Open ETAB file and open the last week challenge

set the load combinations

check whther any erros are there by check list

Click on start Design check option

select design output >longitudinal reinforcement

result of longitudinal reignforcement:

Reinforcement diagram of Grid A:

Max Ast at bottom support = 1920 mm^2

Max Ast at bottom middle = 780 mm^2

Max Ast at top support = 2045 mm62

Max Ast at top middle = 545 mm^2

So providing 2 bars of 25mm

3bars of 20mm at bottom

Provide 2 bars of 25mm and 2 bars of 16mm at top

Reinforcement along Grid 3:

Max Ast at bottom support = 1042 mm^2

Max Ast at bottom middle = 1501mm^2

Max Ast at top support = 1940 mm^2

Max Ast at top middle = 485mm^2

So providing 2 bars of 20mm

4 bars of 16mm at bottom

Provide 2 bars of 25mm and 4 bars of 16mm at top