I renew my objection to any "window" exposed directly to a line of sight leading to the atmosphere on Mars. That atmosphere will hardly slow or filter or burn up incoming rocks or radiation of any kind, leaving a necessity for complex support and emergency repair systems as well as thicker and more complexly produced glass, itself.
Mirrors can be used to bring light and images (properly erected) to properly protected windows, but I have seen no evidence that lack of external lines of sight is the kind of psychological problem that has been evinced in theses parts.
Referring to the ISS or to the LEM isn't of much help as both of those are horrendously expensive and not easily translatable to hectare size exposures.
Quote from: Paul451 on 02/05/2019 06:57 amI'm curious how much difference it would make if the glass wasn't flat but was domed. For eg, doming it inwards (towards the pressure) would put some of the force in compression. AIUI, glass has a compressive strength better than two orders of magnitude higher than its tensile strength.Just to be clear, by "dome inward", I didn't mean the entire structure is inverted, a laI still mean a mundane outward curving shape, but the individual glass panes would curve inwards, to convert tensile forces on the glass into compressive force. (The frame is still tensile.) I'm curious if it would make glass more viable.For eg,
I'm curious how much difference it would make if the glass wasn't flat but was domed. For eg, doming it inwards (towards the pressure) would put some of the force in compression. AIUI, glass has a compressive strength better than two orders of magnitude higher than its tensile strength.
Quote from: Paul451 on 02/06/2019 05:59 amoutward curving shape, but the individual glass panes would curve inwards, to convert tensile forces on the glass into compressive force. Might be a bit of a dust trap
outward curving shape, but the individual glass panes would curve inwards, to convert tensile forces on the glass into compressive force.
The Montreal geodesic dome. Acrylic panes. And why plastic might not be such a good idea...The dome did survive the fire, that happened in 1976, and is still used today, but with an open structure. I want to stay away from exaggerated concern so there are certainly ways to mitigate this. But glass doesn't burn :-) so that's solving the problem at the source. It does make for some lovely symmetries from the interior.I wonder if using small batch processes we might be able to mass produce glass that was tougher than classic soda glass. I'm thinking small panes less than 1 foot across. These would not be safe from sabotage but should survive most likely accidents. Smaller panes would make the result of the break like the one shown less dramatic.
Quote from: lamontagne on 02/13/2019 11:41 pmThe Montreal geodesic dome. Acrylic panes. And why plastic might not be such a good idea...The dome did survive the fire, that happened in 1976, and is still used today, but with an open structure. I want to stay away from exaggerated concern so there are certainly ways to mitigate this. But glass doesn't burn :-) so that's solving the problem at the source. It does make for some lovely symmetries from the interior.I wonder if using small batch processes we might be able to mass produce glass that was tougher than classic soda glass. I'm thinking small panes less than 1 foot across. These would not be safe from sabotage but should survive most likely accidents. Smaller panes would make the result of the break like the one shown less dramatic.Is there any way to make the laminate for Laminated Glass? My understanding is polyvinyl butyral (PVB) or ethylene-vinyl acetate (EVA) are primarily used on Earth, and you can produce Polyethylene relatively easily on Mars. Could that be used? or would you need more.
to run tensile structures from the frame to the foundation, to warp the pressure vessel into a more useful shape,
Quote from: Paul451 on 02/14/2019 07:56 amto run tensile structures from the frame to the foundation, to warp the pressure vessel into a more useful shape, Maintenance safety hazards aside, isn't a tall dome useful in itself?
Quote from: Hominans Kosmos on 02/14/2019 01:18 pmQuote from: Paul451 on 02/14/2019 07:56 amto run tensile structures from the frame to the foundation, to warp the pressure vessel into a more useful shape, Maintenance safety hazards aside, isn't a tall dome useful in itself? Except you aren't starting with a dome. A dome isn't a natural shape for a pressurised volume. So if you want to distort your pressure-vessel into more of a dome-like shape, you are going to need tricksy engineering voodoo.
Not really voodoo:
Geodesic dome with small panes.Small panes undergo much lower stress, and the breakage of a pane is much less important.Lots of joints though.Nodes further away are covered by a concrete dome with a window line. Ground is removed.This is the industrial area of the colony, and the dome houses the cafeteria.
I suggested glass safety film a few pages ago. Surprisingly thin, just a few mills, and it is very tough. Simply stuck to the glass. It could come from Earth at first, then be produced locally.
Hi everybody. I resurrect this old subject. There is something people didn't think about in the 28 previous pages : the ductile/fragile transition for the steel. Medium temperature on Mars is -60 ° C, just the temperature to which steel becomes fragile -> it breaks.So, what can we do ? Warm the steel thanks to little warming chords in it ?Furthermore, another issue : the wind. It can destroy the dome with natural frequency.Another thing : https://en.wikipedia.org/wiki/Creep_(deformation) The creep. On a long time (20 years), steel will strongly deformate, so the lifetime of the dome will be limited, it is sad.