<table cellspacing="0" cellpadding="0" border="0"><tr><td valign="top">Marc,<br/><br/>Strictly from my foggy memory, but I believe it was scuttled.<br/><br/>Joe<a href="http://overview.mail.yahoo.com?.src=iOS"><br/><br/>Sent from Yahoo Mail for iPad</a></td></tr></table>            <div id="_origMsg_">
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                                <span style="font-weight:bold">From:</span>
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                            Marc de Piolenc <piolenc@archivale.com>;                            <br>
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                                <span style="font-weight:bold">To:</span>
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                             <personal_submersibles@psubs.org>;                                                                                                     <br>
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                                <span style="font-weight:bold">Subject:</span>
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                            Re: [PSUBS-MAILIST] concrete                            <br>
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                                <span style="font-weight:bold">Sent:</span>
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                            Mon, Apr 14, 2014 3:30:48 AM                            <br>
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                                        <td valign="top">Really - it sank? Mind you, it did have walls 6 inches thick and very <br clear="none">little freeboard. Any lives lost?<br clear="none"><br clear="none">Marc<br clear="none"><br clear="none">On 4/13/2014 10:35 PM, Joe Perkel wrote:<br clear="none">> It seems to me that with reduced cost materials there is a tendency to<br clear="none">> go big and unwieldy.<br clear="none">> Wasn't that the case with that one fellows concrete sub yacht? It's on<br clear="none">> the bottom of a lake somewhere if I recall.<br clear="none">><br clear="none">><br clear="none">> Joe<br clear="none">><br clear="none">> Sent from Yahoo Mail for iPad <<a shape="rect" href="http://overview.mail.yahoo.com?.src=iOS" target="_blank">http://overview.mail.yahoo.com?.src=iOS</a>><div class="yqt3247188512" id="yqtfd51718"><br clear="none">><br clear="none">><br clear="none">>
 ------------------------------------------------------------------------<br clear="none">> *From: * Sean T. Stevenson <<a shape="rect" ymailto="mailto:cast55@telus.net" href="javascript:return">cast55@telus.net</a>>;<br clear="none">> *To: * Personal Submersibles General Discussion<br clear="none">> <<a shape="rect" ymailto="mailto:personal_submersibles@psubs.org" href="javascript:return">personal_submersibles@psubs.org</a>>;<br clear="none">> *Subject: * Re: [PSUBS-MAILIST] concrete<br clear="none">> *Sent: * Sun, Apr 13, 2014 6:16:35 AM<br clear="none">><br clear="none">> I ran that same 6' diameter 4" shell, but using an ultra high-performace<br clear="none">> concrete with no aggregate, but with steel fiber reinforcement.  Working<br clear="none">> pressure came out to more than 1700 m.  That said, while the compressive<br clear="none">> strength of this stuff is 160 MPa, the tensile is only 8
 MPa, so you<br clear="none">> absolutely have to avoid putting this stuff in tension.  Sphere may not<br clear="none">> be an issue, but a cylindrical hull would probably require some sort of<br clear="none">> pretensioned reinforcement.  Results:<br clear="none">><br clear="none">><br clear="none">><br clear="none">><br clear="none">> On 2014-04-12 21:52, Marc de Piolenc wrote:<br clear="none">>> I had forgotten about the lubricant/plasticizer properties of fly ash.<br clear="none">>><br clear="none">>> Marc<br clear="none">>><br clear="none">>> On 4/13/2014 10:55 AM, hank pronk wrote:<br clear="none">>>> Marc,<br clear="none">>>> We don't get segregation at all, when pumping it we fill the wall and<br clear="none">>>> then let it flow, I call it "ride the wave"<br clear="none">>>> Also pumping the concrete helps hold the concrete together, it
 stays<br clear="none">>>> in a cylinder shape until it hits the wave. We must use fly ash<br clear="none">>>> because the aggregate and sand is washed so well there are no fines<br clear="none">>>> left.  The jagged sand won't flow through the hose.  Fly ash is like<br clear="none">>>> little ball bearings and makes it flow through the hose.  These are<br clear="none">>>> the things that make me think a mold  is the way to go.  Four inches<br clear="none">>>> wall thickness would be a breeze for this mix.<br clear="none">>>> That makes sense that the rock is a cheap filler.  I would still use<br clear="none">>>> the pea gravel mix, I have made a test panel and I drove my bob-cat<br clear="none">>>> over a 2in thick 4by4 panel with no breakage.  I know, very<br clear="none">>>> scientific .lol<br clear="none">>>><br clear="none">>>>
 Hank<br clear="none">>>> --------------------------------------------<br clear="none">>>> On Sat, 4/12/14, Marc de Piolenc <<a shape="rect" ymailto="mailto:piolenc@archivale.com" href="javascript:return">piolenc@archivale.com</a>> wrote:<br clear="none">>>><br clear="none">>>>   Subject: Re: [PSUBS-MAILIST] concrete<br clear="none">>>>   To: <a shape="rect" ymailto="mailto:personal_submersibles@psubs.org" href="javascript:return">personal_submersibles@psubs.org</a><br clear="none">>>>   Received: Saturday, April 12, 2014, 10:40 PM<br clear="none">>>><br clear="none">>>>   Actually, all else being equal, using<br clear="none">>>>   only fine aggregate (sand) will give a stronger mix. Coarse<br clear="none">>>>   aggregate is needed mainly to make the mix affordable - as<br clear="none">>>>   bulk filler, in other words - and also for decorative
 effect<br clear="none">>>>   in some applications where the fresh concrete is brushed to<br clear="none">>>>   show off the aggregate.<br clear="none">>>><br clear="none">>>>   You have to be careful, in very high-strength applications,<br clear="none">>>>   to make sure that the coarse aggregate is chemically inert<br clear="none">>>>   with respect to the cement matrix. Some siliceous aggregate<br clear="none">>>>   will weaken the concrete in the long term by reacting slowly<br clear="none">>>>   with the matrix long after cure.<br clear="none">>>><br clear="none">>>>   Confusingly, very fine silica incorporated in the form of<br clear="none">>>>   fly ash, rice husk ash or silica fume can give a<br clear="none">>>>   super-HIGH-strength mix. The reason for the effect is that<br clear="none">>>>   the very fine silica reacts
 with the alkali formed DURING<br clear="none">>>>   cure and actually strengthens the cement matrix.<br clear="none">>>>   Unfortunately, much of the fly-ash and volcanic ash cement<br clear="none">>>>   on the market is too coarsely ground to harness this<br clear="none">>>>   effect.<br clear="none">>>><br clear="none">>>>   Best,<br clear="none">>>>   Marc de Piolenc<br clear="none">>>>   Ferrocement freak</div><br clear="none">><br clear="none">><br clear="none">><br clear="none">> _______________________________________________<br clear="none">> Personal_Submersibles mailing list<br clear="none">> <a shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" href="javascript:return">Personal_Submersibles@psubs.org</a><br clear="none">> <a shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles"
 target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none">><br clear="none"><br clear="none">-- <br clear="none">Archivale catalog: <a shape="rect" href="http://www.archivale.com/catalog" target="_blank">http://www.archivale.com/catalog</a><br clear="none">Polymath weblog: <a shape="rect" href="http://www.archivale.com/weblog" target="_blank">http://www.archivale.com/weblog</a><br clear="none">Translations (ProZ profile): <a shape="rect" href="http://www.proz.com/profile/639380" target="_blank">http://www.proz.com/profile/639380</a><br clear="none">Translations (BeWords profile): <a shape="rect" href="http://www.bewords.com/Marc-dePiolenc" target="_blank">http://www.bewords.com/Marc-dePiolenc</a><br clear="none">Ducted fans: <a shape="rect" href="http://massflow.archivale.com/" target="_blank">http://massflow.archivale.com/</a><br clear="none">_______________________________________________<br
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