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2 way solid slab with edge and internal beams 1

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insajn

Civil/Environmental
Apr 2, 2017
26
Hello, I hope you all doing well. I wanna ask the people here who have experience in designing 2 way solid slab with beams (manual design).
What is the best method for analysis and design in terms of accuracy and ease ?
 
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The US and Canada both have a version of the Direct Design Method that can be used. Another popular alternative is the Equivalent Frame Method.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
 
Yes I know how to design with "Direct Design Method" but I think it's not that applicable in real life, it's very hard to satisfy all the requirements of the code, let alone its long procedure.

What about Strip method or coefficient method ? ( as manual design )
 
OP said:
Yes I know how to design with "Direct Design Method" but I think it's not that applicable in real life

It's perfectly applicable to real life within the limitations of the method. The method was vetted on countless real world projects in the decades leading up to the development of practical commercial software for use slab design.

OP said:
let alone its long procedure.

Frankly, it's hard to imagine a hand calculation procedure that would be quicker. In Canada, our code has a coefficient method for the, practically instant, design of individual rectangular plates via coefficients. If that's your situation, I can share additional detail.

OP said:
What about Strip method or coefficient method ? ( as manual design )

The direct design is a coefficient method. The strip method and the yield line methods are both valid strength techniques but neither has much to say about deflection which tends to limit their use. I guess you could use them in conjunction with span to depth limits as is often done with the DDM.

A plan sketch of your situation might help us to recommend the most suitable slab design methods.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
 
Thanks. Really appreciate it. By the coefficient method I meant another one, I know little of it but you get a coefficient from a table and multiply it by the load and you get the dostributed load in a certain direction and design with it a 1 meter study area ( thickness of slab and 1000mm width )

And for a typical waffle slab what do you recommend ?
Also can you recommend me some books for slabs ? I want something easy to understand with solved example in it if possible.
 
insajn said:
By the coefficient method I meant another one, I know little of it but you get a coefficient from a table and multiply it by the load and you get the dostributed load in a certain direction and design with it a 1 meter study area ( thickness of slab and 1000mm width )

You're most welcome. That second method that's included in the Canadian code that I mentioned sounds quite similar.

insajn said:
And for a typical waffle slab what do you recommend ?

In many respects, a waffle slab behaves quite like a flat plate slab so any method that works for one stands a pretty good chance of working for the other. Personally, I like to start with the CRSI manual tables.

insajn said:
Also can you recommend me some books for slabs ? I want something easy to understand with solved example in it if possible.

I've never been able to find an all encompassing slab design book to my liking really. Have you settled on the method that you want to use? That would narrow down your book choices.

MacGregor's book has an chapter on slab design, with extensive examples. Most of that is DDM though.

Park's book is good on the theory but doesn't have very extensive examples.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
 
It's probably gonna be DDM using ACI code.
I will certainly check the books. Thanks.
 
In that case, PCA notes to 318 might be a good reference as well.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
 
These days with computers, I would be doing the slab design by one way strip design, with different amounts of load in each direction depending on span lengths, and the beams as one way beams in each direction with the contributing load pattern, either triangular or trapezoidal, depending on the span configuration.

All using equivalent frame.
 
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