Load distribution

[MUHANNAD.ABU_ABDO]

When i take example from structural analysis book .. and distribute the load from two slab to the beams by using Robot .. there's some thing strange in the lenght of trapezoidal  ..

The pic's will illustrates every thing

Robot Distribution

[Rafal.Gaweda · Accepted solution]

Robot assumption: lines indicated in red below are generated as angle bisectors.

 

[MUHANNAD.ABU_ABDO]

So , is this way wrong or right ?

[Rafal.Gaweda]

Ask \ search for assumptions adopted for these lines in the book.
I think bisector assumption is more general, physical.

[MUHANNAD.ABU_ABDO]

In R.C.HIBBELER the most common structural analysis book  distribute the load as in the pic .. i'm really confused .. thanks a lot Rafal for your answer and advice

[Leader_Mohamed]

see this PDF (in Arabic) 05 - (Beams) Loads On Beams Load Distribution

[Rafal.Gaweda]

1. This site is blocked I guess in Europe or link is wrong
2. I do not need it. It is for you to understand how it is calculated in book. I told you how it is done in Robot.

[legar]

Assuming that R.C Hibbeler example slab is multi-span slab in X direction and one-span slab in Y direction, then:

1. A-B & C-D linear supports are not fixed

2. A-D & B-C linear supports could be analysed as fixed for continuous load

so R.C Hibbeler solution is better than simple bisector assumption.

In one of Polish Codes was proposed another general assumption:

[MUHANNAD.ABU_ABDO]

which code is this ?? yield line theory

[Rafal.Gaweda]

Read carefully post above, look at screen shot - .. in frame.

[legar]

Hi,

This load distribution was recommended to use in two old Polish Codes (1979) for concrete structures:

BN-79/8812-01 - "Structures with large panel prefabricates. Design and structural analysis"

BN-79/8812-02 - "Structures with cast in situ walls. Design and structural analysis"

Cheers,

Jerzy

[MUHANNAD.ABU_ABDO]

this is too old .. i think if you have any guide according to EC , BS OR ACI ... because i don't trust this theory maybe change in this days or don't approval with ACI ?

[MUHANNAD.ABU_ABDO]

Look at this pic .. that's completely confuse .. the length 15 feet .. and it's divide equally 5 feet ?

[legar]

Muhannad,

Actually if you want exact solution... just use Robot finite elements not claddings load distribution.

I just want to say, that in some situations bisector assumption is to big simplification in load distribution calculations.

Jerzy

[MUHANNAD.ABU_ABDO]

yes i know that .. but i compare the reuslts between Robot and manual calc

[legar]

---

@Muhannad_91 wrote:

Look at this pic .. that's completely confuse .. the length 15 feet .. and it's divide equally 5 feet ?

Answer:

Simple span slab in both directions and all wall supports the same - so bisector assumption is OK.

Jerzy

---