Bar detailing and placement - Eurocode2 2

[Pretty Girl7]

I have calculated the following for a slab. Obtained the area of steel required in accordance with the eurocode2.
It has fixed end supports.
Compression r/f were not needed. The top reinforcement shown below are for the hogging moment.
I have calculated shear r/f needed as well, but didn't include in the figure below.

The following were calculated by considering the slab is "simply supported" for the easiness of calculation (Although it has fixed ends in real)

For 20 kNm moment --> 400 mm2 of steel
For 40 kNm moment --> 800 mm2 of steel

What I'm not aware is how to place these bars.
I noticed the Eurocode states some of the bar detailing in "clause 8.7". However, I didn't notice the way it should be placed in the slab, especially for the top reinforcement (For 'hogging' moment).
I noticed there's a 'hogging' moment at the ends because of the fixed end supports. So I'm bit unsure how to place bars.

So I assume the following is the way it should be placed.

1. Please confirm if it's the correct way to place the bars shown in figure below.
2. Please let me know how to find the 'X' distance, so I can determine the length needed for the top reinforcement bar.
3. Below is for a slab, however, I'm wondering if this is the same way to place bars for the beams as well.

 

[BridgeSmith]

The reinforcing needs to be adequately anchored into the supports in order to be effective for the negative moment. The critical section (where the largest moment is) is at the connection between the slab and the support.

 

[Pretty Girl7]

@BridgeSmith

Yeah I get it needs anchorage at the supports.

Other than the anchorage at the supports, the top r/f is ok?

I'm trying to understand the concept as well.

And how to calculate the distance 'x'

 

[HTURKAK]

For your case ,

- at least half the span reinf. shall extend to the fixed support with 0.5 tension lap

- the hogging reinf. ( support reinf. ) shall extend Lb ( tension lap ) to the fixed support ..


P.S. Copy and paste from ( IStructE/ Standard Method of Detailing Structural Concrete )

I cannot give you the formula for success, but I can give you the formula for failure..It is: Try to please everybody.

 

[Pretty Girl7]

@HTURKAK
Thank you. Further, do you know how to find the 'X' distance from the supports?

 

[HTURKAK]

These are point of contraflexure ( moment zero points ) ..
In your case ( both ends fixed , X=Y= 0.21 L

You may find at strength of materials bokks or simply solve the moment equation ..
In practice , 0.20L -025L may be assumed for reinforcement curtailment..










I cannot give you the formula for success, but I can give you the formula for failure..It is: Try to please everybody.

 

[BridgeSmith]

Further, do you know how to find the 'X' distance from the supports?

I don't wish to be rude, but if you need help with something that basic, you should not be attempting structural design.

 

[Pretty Girl7]

@HTURKAK
Thank you for the information with clauses. It helps.
And thank you for the book reference. I'll go through it