I have worked in building maintenance and repair. One thing that is extremely hazardous to a concrete building is too much water. I have seen many concrete planters that crack and result in water leaks for lower levels. Standing water in concrete structures is a huge no no. I do not have a lot of experience in engineering on this matter, but whenever I see a solar punk sky scraper with vegetation on its exterior, I think “cool, but maintenance and inspection must be horrible! Repairs must cost a fortune when those roots and moisture degree the concrete.”
What engineering controls does one need to create a durable structure while exposed to constant moisture needed for vegetation, and the vegetation itself? I know there are green sky scrapers with gardens all over. What is the maintenance of those structures? Do they hold up\last as long as bare concrete structures?
Water is actually good for concrete. Well… more like it doesn’t care. https://www.youtube.com/watch?v=b43Iz2OoUNk
Problem is that iron rebar in the concrete rusts and expands cracking the concrete. https://www.youtube.com/watch?v=PLF18H9JGHs
PS Sir Martyn Poliakoff, the professor in the first video, studies “green chemistry”. He’s a great man.
Thanks for the vids. I’m not sure “water is good for concrete, or doesn’t care” is accurate. In a controlled environment that may be true, however with corrosion from polluted rain (the lime in concrete is dissolved with acid rain), expansion and contraction (especially with freeze thaw cycles), and biological processes that may be encouraged to grow in damp conditions, water is pretty bad for concrete; these are examples of what I’ve encountered that caused degrading concrete structures.
That said, I was thinking about it more and things like dams and drilled t shaft concrete piles are obviously exposed to constant water. I’m wondering if what I experienced has to do more with exposure to aerobic and temperature fluctuating environments as opposed to drilled shafts and dams which would be more isolated from those conditions I described above.
Even if water itself isn’t the primary mode of failure, I guess my point still remains regarding the vegetation of "green"buildings; roots and what not definitely will start to degrade concrete.
Thanks for the comment, it gave me some points to think about.