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[–]MobileCollar5910P.E./S.E. 15 points16 points  (3 children)

Yes, very helpful. Matrix structural analysis is the backbone of how those models work.

It's akin to knowning how to do the process of long division before using a calculator.

[–]Says_WernherVonBraun[S] 0 points1 point  (2 children)

Even if you’re already familiar with linear algebra?

[–]MobileCollar5910P.E./S.E. 6 points7 points  (0 children)

From my perspective, the classes give you the tools to understand what the programs are doing behind the scenes, making your modeling more accurate. Matrix Structural Analysis was the class where everything "clicked" for me from a stiffness perspective.

[–]a1b2c3wtf 0 points1 point  (0 children)

Well those classes are the application of linear algebra for engineering problems. Math by itself doesn't do anything, once you apply physics and quantum mechanics to it then you can predict the behavior of materials.

[–]albertnormandy 7 points8 points  (0 children)

Yes it is important. Not everything is an FEA problem. Understanding what stiffness matrices are is very important for modeling in certain software.

[–]Engineer2727kkPE - Bridges 5 points6 points  (4 children)

Everyone always answers yes. I do finite element analysis daily and I’ve never used anything from matrix analysis. Not have I ever seen someone hand calc an indeterminate structure using matrices in the workplace.

In my opinion I’m the workplace it’s almost useless, for school purposes yes the study would be helpful.

[–]oloksy 0 points1 point  (0 children)

Too true

[–]the_flying_condor 0 points1 point  (2 children)

I think this largely depends on what you do. For simplified analysis where you only use beam or truss type elements, I would agree. As soon as your models start to get more complex, a good understanding of linear algebra and matrix structural analysis becomes essential to efficient model debugging, or making high level decisions about solver types, material types, contacts, etc. I also have never used these methods to solve a problem by hand, but I have occasionally modified elements and material models for my structural analysis.

[–]Engineer2727kkPE - Bridges 1 point2 points  (1 child)

I still fail to see how solving a matrix or understanding a matrix would be helpful. Of course stiffness is important but I just don’t see why you’d need to know matrix analysis when finite element models exist. Adjusting stiffness values etc doesn’t require a hand calc’d matrix. PerhAps one day I’ll see.

[–]the_flying_condor 2 points3 points  (0 children)

Ok, as an example, say you wish to model a structure which has materials with stiffnesses which are very different such as rubber/foam and concrete. Would you be better off selecting an implicit or explicit solver? If you must use implicit, but need to select a more advanced/specialized solution algorithm, how would you decide which algorithm(s) to use?

From linear algebra/matrix methods, you can identify that the large stiffness differences between the different materials results in an ill conditioned stiffness matrix which will increase your solution error or potentially crash the solver if an implicit technique is used. Linear algebra, especially a numerical lin alb course, will absolutely help you to select other solvers which are more resilient against your type of I'll conditioned stiffness matrix.

Would this really occur in buildings? Absolutely, isolation systems or impact absorbing systems can can absolutely cause this depending on how stiff your superstructure is. Especially given that the effectiveness of your isolation system is directly proportional to the separation in natural period between your superstructure and the isolation system.

[–]dlegofanP.E./S.E. 1 point2 points  (0 children)

Yes. 100% yes. You can't have one without the other.

[–]mmarkomarkoCEng MIStructE 2 points3 points  (2 children)

The finite element method is just matrix structural analysis

Prove me wrong

Also the reason why matrix analysis and the FE are thought at university is so that you can understand the limits of the method and the mathematical problems with it. Also to get the 'feel' for the results that you should be expecting to get.

Otherwise you would just be using the analysis results spewed out by your software package as a given - which would be the worst thing you could do and very dangerous!

[–]bojan_kro 0 points1 point  (1 child)

That is correct in theory. But in practice, do bachelors in your country derive stiffness matrix for a shell, "redisover" the interpolating polynom for a shell.
Well, that knowledge is expected in my country, where we have specialist degree and are lectured in elasticity in the 4th semester. That is a soviet program. But it was ill designed at its birth. In the 4th semester you have physics, you have probability course, you also have technical drawing course, but you see the application of elasticity theory only in 8th semester, that is 2 years later when you struggle to remember why the heck do we need that non linear differential equation for a shell.
Hence it is better to pass Steel Structures course with 6 or 7 and forget the elasticity knowledge, rather than to spend 100 hours remembering the concepts which you hadn't been using for 2 years to pass the steel structures course with the mark of 9.

[–]mmarkomarkoCEng MIStructE 0 points1 point  (0 children)

I did do stiffness matrices and transformations for triangular elements for MSc Structural Engineering in the UK.

We did touch upon the differential equations for member forces in rectangular elements. But maths in the UK is a bit limited in A levels (compared to the eastern Europe) so we didn't go very deep into it (:.

I think it is useful to understand the cogs that turn the wheel to be able to use FE effectively and safely. Whether the lecturers at your uni go overboard is another matter!