membrane stress
membrane stress
(OP)
I am looking for software that considers membranes (for example aluminum 48"x .02"x 120") with concentrated loads. Presently using RISA-3D but can not sucessfully convert plates into membranes. Roark is no help with membranes and concentrated loads





RE: membrane stress
RE: membrane stress
RE: membrane stress
wlw32
RE: membrane stress
This method is widely used by metalurgical engineers, and less by structural engineers. See for example, Reinforced Concrete Design by Wang & Salmon, under a chapter dedicated to yield line theory for reinforced concrete slabs. The analysis is based on statics equilibrium (or as Swang stayted by means of virtual work) of the membrane after yielding occurs on certain lines that turns the problem to an statically determinate structure. The method can be applied for any membrane slab of any kind of material. You might be interested if you know that Rusians applied this method by doing tests on ice slabs
RE: membrane stress
I'm looking for approximate solutions at this stadge, so does Wang & Salmon's text provide some approx. formulae for different cases of conc. loading?
Or would one have no choice but to consult FEA for this?
RE: membrane stress
Thanks.
RE: membrane stress
RE: membrane stress
The thing is that like wlw32 I'm looking at concentrated loads or loads applied in small circular/rectangular regions on the middle of the steel membrane.
These loads produce large deflections. So far I've been at a loss in trying to track down theoretical sources that can provide some sort of approximate formulae (upto 10% error is OK) for this case study.
FEA is a last resort really (I have very limited access to a decent package at the moment), so any extra help in finding mechanical solutions would be much appreciated.
RE: membrane stress
Only circular membranes at the moment: hope this is OK for your needs.
Please note that the solution for membranes is strongly non linear: no superposition applicable!
Scranton: clamped membranes, if you mean by that with no edge rotation, makes no sense for membranes. If you mean held end (no radial displacement at support) then it's OK.
prex
motori@xcalcsREMOVE.com
http://www.xcalcs.com
Online tools for structural design
RE: membrane stress
RE: membrane stress