7. 3 dimensions and matrix notation

Direct Stiffness Method for Truss Analysis
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Questions and discussion for this lecture live here. Fire away by hitting Reply below :fire:

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Hi Sean,

I wonder if Slides of the previous Lectures are available. I can’t see in “File” or “link”

thanks

Marco

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Hey @marco.origgi,

I’m afraid I don’t have downloadable versions of the handwritten notes. The idea here is that you build up your own versions by writing alongside these lessons and making additional notes as you work - after 10 years of teaching in person, I’ve found that this makes for a much more effective learning experience.

Hope you’re enjoying the course :+1:

Seán

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Hi Sean,
no problem, I was taking notes during the Lectures, as usual. The course is interesting, for an old Structural Eng. like me. actually at my “time” I used Fortran to write my FEM programs (beams and Shell elements); now I am facing to Python… :smiley:

regards

Marco

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Haha…the same thing will happen to us all one day Marco…Python will eventually become Fortran :roll_eyes:
S

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@6.15 i believe there should be a factor of 1/2 in the equation, unless the strains are engineering strains (then it would be gamma and not epsilon) given that linearised strain is E = (1/2) [grad u + grad u^T]

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Hi @Chris_Powell-William

Yes, this is a good point. However, in this course we’re using the engineering strain which is quite common in FE formulations. I think the confusion comes from me just using a different symbol to what you’re used to - perhaps I should have also explicitly stated it.

Thanks for posting - helps everyone out!

Seán