Design of reinforced concrete helical staircase using Euroode2 3

[tadjou laura]

Hi

My name is Boris. A new member of the forum.

Usually in Eurocode for design of reinforced concrete theoritically we read from CHART(TABLES 177 of REYNOLDS AND STEEDMAN, 2005]. From this chart we can easily do the structural analysis or calculate the forces (vertical shear, radial horizontal shear, Axial forces, Torsion, horizontal moment, vertical moment at different angles.

Where can i find this chart please?? I Searched it on google but can't find it. please is there any document where i can get this chart from??

 

[tadjou laura]

Did some load set combination for a 5span beam (in frame) but have some problem with the scale in the printing of the CAD file. please is there any way to do so adequately?

 

[BulbTheBuilder]

I will skip the vibration analysis for concrete frame for office use. Unless this is a medical facility

The retaining wall is very simple, get your earth pressure, find the moment, and find the reinforcement (15 mins tops)

For shear wall, determine your lateral loads, wind or seismic. Simplify the system as a cantilever beam and check the overturning moment. All these are preliminary, so you don't go back and forth with robot model.

For the building frame, just remodel the structure in Robot. I looked at image you attached, and you had upper floors column look bigger than the lower floors. Keep the model simple.


By the way, what are you to do for this project? What's the main scope?

I like this layout better. Few comments see attached

 

[tadjou laura]

Thanks for the final review Sir. Here's what we're supposed to do

The analysis and design of these GA plans

-We choose a frame of our choice and do the analysis and design of columns, beams and slabs.(manual calculation of these elements in frame are obligatory + load takedown).

I choose the back face because there are circular columns, and a rectangular columns.


-the analysis and design of variety of element is also obligatory, like these 3 different types of staircases,shear and retaining wall .

-Foundation design is a must

-The final result is the reinforcement manual+ software calculation, which are supposed to be compared and have thesame result unless some low percentage error

 

[tadjou laura]

All calculation are required to be done in Eurocode 2

 

[tadjou laura]

but globally, it is required that all the elements in the GAplans should pass in ULS and SLS even visually.

 

[tadjou laura]

The slab is almost at the limit of deflection of 25mm. We have a high required reinforcement of 7000mm2 that robots find's it difficult for provide even with bar size of 32mm.

 

[tadjou laura]

but with the lack of time, will take the result of the analysis in robot and do the design manually as you said Sir.

 

[BulbTheBuilder]

Slab reinforcements are typically called out per meter. Example 600mm2/m, note that during your submission. 32mm@150 in a slab is extremely big and a lot.

but with the lack of time, will take the result of the analysis in robot and do the design manually as you said Sir.

Sounds like you know what to do. Do you have/know other folks working with Robot, so you work with a group? Doesn't look like you are good at using the application. Team up with someone, work with a group.... they might help you thru some of the problems as you don't have time

 

[tadjou laura]

thanks for the tip Sir .

i'm in a foreign country far from my classmate. but i think i can handle RSA.

Just from fixing the spacing to 20mm@100mm and it worked.

The most important problem is the raft foundation calc and verification of the manual calculation of all the element. which if have a little bit of time could look into it when i'll send my result and questions. (i.e the calculation notes of robot compared to the manual calc). if you agree Sir.

Thanks for your time

Boris

 

[BulbTheBuilder]

You're making progress.

https://www.concretecentre.com/Reso...Design-Concrete-Structures-to-Eurocode-2.aspx

For the manual calcs, refer to the link. Check with your library if they have one available. Very good resource, I used to use this back in the early 2018

You can also check Reinforced Concrete Design by J. H. Bungey, R. Hulse, and William Henry Mosley. It is an excellent book as well but not, it's in BS8110

Design of Structural Elements: by Chanakya Arya is great as well. It doesn't feel advance to me but good for school project

 

[tadjou laura]

Hi Sir@BulbTheBuilder;

Thanks to all documents and recommendation books, i've just finished the manual calculation+verification software calculation of RC beams+ fire provisions. But there's still a difficulty to fire provision for columns. Thanks to the book send before , solve the effective length condition with boundary conditions, but now i face challenge with the e<0.15b. Change the section iterativetly but keeps on having thesame error. please is there a way i can deal with this ??

Thanks for your help and kindness

Boris

 

[BulbTheBuilder]

You're welcome.

e exceeds 0.15h(b):- what's the value of e and h? Make b the subject of your equation and determine the required b to make your column stocky. That should work for you. It been long since I used Eurocode so I can't get into code details and specifications. But make column bigger

 

[tadjou laura]

Thenks Sir. finaly find the way through in fire provision. In addition made the correction in the GA plans as recommended. Can i get your final point of view on this Sir?

Thanks

Boris

 

[BulbTheBuilder]

The comments are typical for most plan.

The plan set looks good. I know you're a student but don't be afraid to go bigger with your sizes if needed. Talking about your beam widths....for constructability, I'd recommend +450mm wide interior beams so you can fit your rebars. P.S you dont' need to do this is the 300mm is okay.

Also, add grids and levels to your final plan before submission.

 

[tadjou laura]

Hi Sir;

Many thanks for the feedback and corrections. Appreciate a lot. will update the GA plan

Here's the BMD and SFD with redistribution attached+ reinforcement details. What do you think of the bent up bars at midspan, it is neccessary? , inserted it considereding high SF. What about the hooks at end support Sir???

Please in addition, may i know your name Sir, want to insert in the Master thesis word file, if you don't see a problem in that.

 

[BulbTheBuilder]

You're welcome. Review your model, your beam bending moment doesn't reflect the framing. The bending moment shows you have three supports. See attached.

You can use the name, "Bulb the builder" or any random name preferred. I don't put personal info on this forum.

 

[tadjou laura]

A huge thanks Sir!!, I can't beleive i couldn't see that!!. I wouldn't be in peace without saying a Huge thanks to you for this project, cause you're the one that helps with a lot of corrections . Unfortunate i can't even know the professor's name that's giving me a huge hand for this, without even knowing me.

 

[BulbTheBuilder]

You're welcome. That's exactly what this forum is for...One day, you can also offer support/answers to those with questions. Wishing you the best with your final project!

 

[tadjou laura]

Thanks Sir. it's precisely on the 16th of september, there's a bit of with some final corrections, this week at least. Like for the raft, the form of the structure makes it not to be rectangular, so it's a beat difficult to find the centroid for manual RC design purposes

 

[tadjou laura]

For most foundation textbooks i found the raft is ractangular, so it's a little more easy to design compared to this shape i'm constraint to have due to the property limit of the building