# Civil Engineering - RCC Structures Design - Discussion

Discussion Forum : RCC Structures Design - Section 1 (Q.No. 4)
4.
The minimum number of main steel bars provided in R.C.C.
rectangular columns is 4
circular columns is 6
octagonal columns is 8
all the above.
Explanation:
No answer description is available. Let's discuss.
Discussion:
23 comments Page 1 of 3.

Surajit biswas said:   7 months ago
Can we provide an unequal number of bars (eg- 7 nos, 9 nos, 11 nos, 13nos) in a column? if not why? Please explain to me.

Rajendra D said:   4 years ago
It is mentioned in IS 456:2000, clause 26.5.3.1 (c and e).

Shubham Arbat said:   5 years ago
The minimum vertical space of the main reinforcement in RCC beam is the diameter of the larger bar or two-third the nominal maximum size of coarse aggregate.
(1)

Sameer Sopori said:   6 years ago
@Kiran.

For circular column you can not use 4 bars, For Circular column, you need minimum 6 bar.

And for Rectangular shape of the column, you can use 4 bars minimum.

Kiran c said:   7 years ago
4 number of bars.

Anuj said:   7 years ago
How many number of minimum main bars provided in a RCC beam?

(a) 2Nos
(b) 3Nos
(c) 4Nos
(d) 6Nos
(2)

Ashok said:   7 years ago
What is the minimum dia of bar used as a surface reinforcement?

I want to know the min bar size.

Shambhoo Kant Jha said:   7 years ago
Minimum diameter for longitudinal bars are 12 mm. It is circular as for given volume, surface area is maximum. Hence more surface area for bond with concrete. In circular, it is 6 bars as it can be compared with hexagonal and 1 bar supposed in each corner for proper placing of lateral ties.

Sukanta Das said:   8 years ago
What is the minimum diameter used for the longitudinal bars?