Civil Engineering Association
how to develop the concept structural design or choose the structural system - Printable Version

+- Civil Engineering Association (https://forum.civilea.com)
+-- Forum: Various (https://forum.civilea.com/forum-6.html)
+--- Forum: Free Discussion (https://forum.civilea.com/forum-46.html)
+--- Thread: how to develop the concept structural design or choose the structural system (/thread-56841.html)



how to develop the concept structural design or choose the structural system - apir064 - 02-04-2022

Hi All,

I am wondering if this has been discussed before or not, but I am interested in seeing how you guys make decisions regarding the structural systems you use in the project.

If we considered just basic structural systems such as RC moment frame/ RC shear walls/ Steel moment frames/ Braced steel frames (EBF/CBF). How do you choose between these systems and how do you develop the preliminary/concept model?

Is there any book you recommended regarding developing the conceptual/Preliminary structural models?

Regards,


RE: how to develop the concept structural design or choose the structural system - Dell_Brett - 02-04-2022

A very interesting question!

There are numerous factors that are necessary to make an appropriate choice:

- Architectural design;
- Entrepreneur's preference;
- Regional trends;
- Economic viability of alternatives at the implantation site;
- Know-How of the region's builders and installed logistics;
- Etc...

But, I believe that the main component is the EXPERIENCE of the structural engineer.
Experience makes you sure that certain structural conceptions are the most appropriate! Make it intuitive!

I think that this is not found in its fullness in books, articles, forums... But it is the result of a lot of work (and dedicated time) to acquire this expertise!.

The "learning curve", or professional maturity, is accelerated with studies and, above all, practical experience! But she has her time!

I have over 40 years of experience in structural projects! To this day, it is very common for me not to be sure for some projects what would be the best design and construction technique?
- Conventional reinforced concrete;
- Precast concrete;
- Prestressed concrete (in particular on slabs --> Post-tensioned)
- Steel structure;
- hybrid solutions?

Often the contractor pays me to pre-size two (or more) alternatives when in doubt!
This allows for reliable data (not assumptions) about the best viable alternative.


RE: how to develop the concept structural design or choose the structural system - apir064 - 02-04-2022

(02-04-2022, 09:31 AM)Dell_Brett Wrote: A very interesting question!

There are numerous factors that are necessary to make an appropriate choice:

- Architectural design;
- Entrepreneur's preference;
- Regional trends;
- Economic viability of alternatives at the implantation site;
- Know-How of the region's builders and installed logistics;
- Etc...

But, I believe that the main component is the EXPERIENCE of the structural engineer.
Experience makes you sure that certain structural conceptions are the most appropriate! Make it intuitive!

I think that this is not found in its fullness in books, articles, forums... But it is the result of a lot of work (and dedicated time) to acquire this expertise!.

The "learning curve", or professional maturity, is accelerated with studies and, above all, practical experience! But she has her time!

I have over 40 years of experience in structural projects! To this day, it is very common for me not to be sure for some projects what would be the best design and construction technique?
- Conventional reinforced concrete;
- Precast concrete;
- Prestressed concrete (in particular on slabs --> Post-tensioned)
- Steel structure;
- hybrid solutions?

Often the contractor pays me to pre-size two (or more) alternatives when in doubt!
This allows for reliable data (not assumptions) about the best viable alternative.

I agree with you that previous experience and design constraints and others play important roles in decision making.

However, I think we could come up with some general principles (more from technical aspects) to make a decision about the main lateral and gravity systems, especially for mid-rise buildings, there are various options.

Let's say that in an 8-storey building, the architectural features allow us to have any hybrid systems (shear wall + Frames), RC frames, Steel moment or braced frames (high seismic actions). From the technical point of view, what would you choose and why?

Cheers


RE: how to develop the concept structural design or choose the structural system - Dell_Brett - 02-05-2022

OK!
Being pragmatic, for a watertight example as suggested (8-storey building), with an architecture that allows a wide range of solutions, it is obvious that the best solution (the one that the contractor wants) is the one that has the LOWEST COST!

That said, we return to the initial reflection: -Which of the options has the lowest final cost?

There are books and publications dealing with the advantages and disadvantages of each structural solution. It is also possible to resort to cost indicators of the various alternatives, however, they must always be verified and certified for the contracting party, which, as said, may have to do the pre-dimensioning of two or three alternatives to be sure. more economical!
Naturally, observing what is most usual for the same work pattern can be a first and great indicator.

In the region where you operate, study what is most used and what the trends are...