[PSUBS-MAILIST] fiberglass as hull material

[hank pronk via Personal_Submersibles]

It should also be noted that there is no cost saving with fiberglass.  In fact I would guess fiberglass will cost twice as much as steel.
Hank
--------------------------------------------
On Fri, 11/21/14, Sean T. Stevrnson via Personal_Submersibles <personal_submersibles at psubs.org> wrote:

 Subject: Re: [PSUBS-MAILIST] fiberglass as hull material
 To: "Personal Submersibles General Discussion" <personal_submersibles at psubs.org>
 Received: Friday, November 21, 2014, 5:37 PM
 
 Fiber reinforced resin matrix composites cannot be
 modeled the same way as isotropic materials, owing to the
 strongly directional behaviour compared to the axes of
 curvature in pressure hull forms. The composites also
 introduce new modes of failure, such as interlayer
 delamination. That said, they can and have been used as
 pressure hull materials, but you generally will need to
 custom model the behavior with regard to your hull geometry.
 In a typical composite layup, the average material
 properties are approximately equal to the average material
 properties of the matrix and reinforcement in proportion to
 their respective volume fractions, but failure modes are
 still dictated by the weaker or more brittle material.
 Performance is also dependent on layer thickness and
 principal fiber orientation in each layer. Fiber reinforced
 composites will tend to fail catastrophically in a shear
 mode, versus yielding inelastically as with steel, so you!
   need to
 be very confident in your strength analysis to go this
 route. Unless you have a strong background in engineering,
 it may be more trouble than it's worth for a
 homebuilder.
 Sean
 
 
 
 
 On November 21, 2014
 9:24:08 AM MST, roberto alvarez via Personal_Submersibles
 <personal_submersibles at psubs.org> wrote:
 Hi did some
 one have information regarding the use of fiberglass cloth
 as hull material,  want replace the info on the calc 
 
 
 Personal_Submersibles mailing list
 Personal_Submersibles at psubs.org
 http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
 
 -----Inline Attachment Follows-----
 
 _______________________________________________
 Personal_Submersibles mailing list
 Personal_Submersibles at psubs.org
 http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles