Building Engineering Log

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Sat Aug 27, 2016

This is a complex matter. The problem n°1 for me is that the job done by one engineer in one part of the world will be almost useless in other parts of the world. This is because most of the hypotheses used when designing structures are based on local norms. So you could have, let's say, one US engineer who will design a structure that holds, and respects US norms. But to build that structure in Europe for example, you will need to incorporate - and prove that you used - all the local norms, which will basically make you redo all the calculations from scratch, these norms mostly give you parameters to design with, not things you can simply "add" afterwards. Also, remember that the ground conditions have a very big impact, so every new location can require heavy changes.

This is specially true for reinforced concrete, which is anywhere in the world a subject very strictly regulated by norms.

We work with a couple of structural engineers here in São Paulo (our favorites are those guys who are true artists), but none of these guys will do volunteer work, or, probably, be interested in this "crazy" project :) Also most here in Brazil don't speak much english. You must also consider that, while for an architect, working "the open-source way" might sound interesting (good publicity, a chance to show what you can do, and reasonable chance to be called to do adaptations if someone uses your work), the same is not true for a structural engineer, most of his calculation work could then be reused without calling him again. So their interest in doing open-source, volunteer work will be very low.

One person I would recommend is Bernd Hahnbach, who is "our structural engineer" at FreeCAD. He's basically the most active person behind the FEM functionality development. He was interested in working with one of the projects we did with but t ended up not going further... Bernd has a fulltime job, though, so his availability and interest might be low. There are more structural engineers hanging around there, though, don't hesitate to give a shout on the forum there if you are interested in finding them..

FreeCAD cannot be used directly to do the structural calculations. So far this still needs a human :) But it is more and more becoming a good tool to incorporate these calculations and design structures. With a litle push we could go very close to what commercial platforms do.

But really, the job of the structural engineer, more than design the structure, is to dimension the structure. With an architect who understands enough of structure design, you can go very far without engineer, and only have it enter the dance very late. Not wanting to push me forward of course, but that's what we try to do as much as possible (ex. we design basically all the structure ourselves, with a little bit of consulting, the actual calculation will come at a much later stage). In the case of a single-family house, the need for a structural engineer is very minimal, or even non-existing.

So you could consider doing all the "generic" work without engineer, and prepare to contract a local engineer only to do the final, local part, that you will have reduced to a minimum.

Some principles I would consider:

- Use as little reinforced concrete as possible. Steel and wooden structure are far less regulated, and it is much easier to use sections that will satisfy all the norms worldwide. - Make the whole structure as lightwight as possible (use some form of anchoring if it becomes so light that wind can become an issue). This will remove impact on the ground, and simplify foundation work a lot. Some very lightweight structures can have basically no fundation at all. - Share as much design as possible and encourage technical discussions. This should help going towards a more universal design. - Forget about International Building Code, which AFAIK has not much of international, and is basically only used in a couple of US states... I would concentrate on principles that will make the design truly universal and adaptive.