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Location of the floor plate (slab) reinforcement


Kirill
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In this topic I would like to talk about location of the floor plate reinforcement.

This is a continuation of the topic started in this topic: 

I hope that I am not violating the rules of the forum by creating this topic. In my opinion it's another topic and idea.

Problem: There are basement walls and should be basement slab (floor or plate) connected to them. Connection of walls and slabs we discuss in this topic👆.

Here I would like to talk about horizontal bars of slab. First of all bars of bottom. The drawing of basement are attached. In basement slab should be hole for future stair (red rectangle). Also there are very weak zones (red dotted line on one drawing and blue zones on another one), they are door overlap and have thickness ~150 mm (It's not a wall). 

There will be bottom bars (main and non main bars) and upper bars (main and non main bars), criss-cross, step between bars is 200 mm. I am going to use 12 mm bars, max length is 11700 mm. The max length of house is more than 11700, so I should use connections.
Let's start from the very bottom. I found some solutions and advises. I also attached them. 

Here is some rules that I found:

1) Connection for bottom bars should be above the walls. Not in the center!!!

2) Connection should be 40*d (12 in my case), but I decided to use no less than 700 mm.

3) If there are many bars located along at a distance of 200 mm from each other, the connections must also be at different distances

 

I tried to use all of them and created drawing with help of all these rules. You can see result. On the drawing you can only see BOTTOM MAIN bars. I didn't draw all of them, because I was not sure about my solution. I just draw bars (red lines) in most important in my opinion areas. In the final version, the fittings will be located at a distance of 200 mm from each other. 
I tried to use all connections above the walls (yellow rectangles). Is it correct? I don't know where bars should have connections above the doors overlaps. Should these connections be located above these overlaps or not? Where they should be?

So, the most important questions:

1) Are the connections in the drawing located correctly?

2) How should these connections be positioned when the fittings pass over the doorways?

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  • 4 weeks later...
On 1/29/2022 at 3:40 PM, Kirill said:

1) Are the connections in the drawing located correctly?

Yes, looks good. The concept picture that you attached about rebar detailing is correct. I am attaching it below for clarity.

image.png

 

On 1/29/2022 at 3:40 PM, Kirill said:

2) How should these connections be positioned when the fittings pass over the doorways?

Depends on door height. If the door height is to the top of slab normally slabs are poured with beams and the beam and in that way the beams extend over the doors. Where doors are shorter, there is a sill beam placed. 

Thanks.

 

 

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