You will not convert anything, you could (1) apply 1000N on the top plate, the top plate would then converge to the equilibrium position which will correspond to a force of 1000N exerted on spheres, or (2) load the sample at constant strain rate until the force on top plate reach 1000kN.
Remember that the total force on a body is already defined somewhere. Here, the total force on a plate is simply the sum of contact forces exerted by spheres. You don't need to compute anything if all you need is to get this quantity. You should check what is done in TriaxialStressController perhaps. Or perhaps I still don't understand, and what you need is analysing forces one by one, in that case you'd have to traverse all contacts in the simulation and check which of them are sphere-plate contacts. Bruno kan a écrit : > Thanks, Bruno, > > I think I did not describe the question clearly. > my question is how to get the force from the force boundary. for > example, we use a rock sample to do the compress test. so we have to > force boundary from the upper face and the the lower face. then how to > get the foce on each grain from the boundary? we will say the force > applied on the surface is 1000N, and the area is around 5 square cm, > then how to convert the 1000N to the particle which contacting with > the boundary (like a steel surface)? > > Regards. > > Kan > > > Message: 2 > Date: Fri, 25 Jan 2008 10:53:29 +0100 > From: Bruno Chareyre <[EMAIL PROTECTED] > <mailto:[EMAIL PROTECTED]>> > Subject: Re: [Yade-users] Yade-users Digest, Vol 19, Issue 15 > To: [email protected] <mailto:[email protected]> > Message-ID: <[EMAIL PROTECTED] > <mailto:[EMAIL PROTECTED]>> > Content-Type: text/plain; charset=UTF-8; format=flowed > > I don't really understand your question. There is no conversion from > stresses to forces, the conversion goes from forces to stress. > If you find a way to explicitely convert stresses into forces in a > sphere packing with friction, well... you should apply for the Nobel > Prize ;-). > > Bruno > > > > > > kan a ?crit : > > Vaclav, Bruno > > > > Thanks to both of you very much. > > Then how about the convertion from the stress to the force on each > > particle, where the stresses are from the boundary ? > > > > kan > > > > -- > > _______________ > Chareyre Bruno > Maitre de conference > > Institut National Polytechnique de Grenoble > Laboratoire 3S (Soils Solids Structures) - bureau E145 > BP 53 - 38041, Grenoble cedex 9 - France > T?l : 33 4 56 52 86 21 > Fax : 33 4 76 82 70 43 > ________________ > > > > ------------------------------ > > _______________________________________________ > Yade-users mailing list > [email protected] <mailto:[email protected]> > https://lists.berlios.de/mailman/listinfo/yade-users > > > End of Yade-users Digest, Vol 19, Issue 17 > ****************************************** > > ------------------------------------------------------------------------ > > _______________________________________________ > Yade-users mailing list > [email protected] > https://lists.berlios.de/mailman/listinfo/yade-users > -- _______________ Chareyre Bruno Maitre de conference Institut National Polytechnique de Grenoble Laboratoire 3S (Soils Solids Structures) - bureau E145 BP 53 - 38041, Grenoble cedex 9 - France Tél : 33 4 56 52 86 21 Fax : 33 4 76 82 70 43 ________________ _______________________________________________ Yade-users mailing list [email protected] https://lists.berlios.de/mailman/listinfo/yade-users
