<html><head></head><body><p dir="ltr">Build a geodesic dome out of rebar, cover it in mesh, and pour a sphere of ultra high strength (no aggregate) fiber reinforced concrete around it, vibrating the hell out of it to eliminate bubbles. The shape might be a bit strange, given that your openings need be reinforced with a pad sufficent to replace the material missing in the opening, and your concrete shell is quite thick. You'd have to build a bunch of them, strain gauge them all, and lower them over the side until failure.</p>
<p dir="ltr">Sean<br>
</p>
<br><br><div class="gmail_quote">On April 12, 2014 6:40:53 AM MDT, hank pronk <hanker_20032000@yahoo.ca> wrote:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<pre class="k9mail">Hi Sean,<br />Thank you for the calculation. That figure is quite interesting, considering it is only 30mpa. I wonder if re-enforcement is beneficial given the sphere shape. <br />Imagine if you could figure out a safe way to make an opening in the sphere for ports and hatch, you could build a hull for under 1,000 dollars. Amazing!<br />Hank<br /><hr /><br />On Fri, 4/11/14, Sean T. Stevenson <cast55@telus.net> wrote:<br /><br /> Subject: Re: [PSUBS-MAILIST] concrete<br /> To: "Personal Submersibles General Discussion" <personal_submersibles@psubs.org><br /> Received: Friday, April 11, 2014, 10:34 PM<br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> Hank,<br /> <br /> <br /> <br /> There are countless varieties of concrete, all with<br /> different<br /> mechanical properties, so it is difficult to make an<br /> effective<br /> comparison, but just for fun, I ran your scenario<br /> (6' OD, 4in<br />
thick shell) with average material properties for<br /> ordinary<br /> concrete, and it turns out it's good to over 1000<br /> fsw! See below.<br /> <br /> <br /> <br /> Sean<br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> -----Inline Attachment Follows-----<br /> <br /><hr /><br /> Personal_Submersibles mailing list<br /> Personal_Submersibles@psubs.org<br /> <a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br /> <br /><br /><hr /><br />Personal_Submersibles mailing list<br />Personal_Submersibles@psubs.org<br /><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br /></pre></blockquote></div><br>
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