HiIm afraid if anyone could help me to use confinement convergence method in plaxis?
Im looking forward to find how to calculate beta value.
Ahmad,
The question you asked combines all tunnel theories and does not have a simple answer. It is the most important part of the tunnel models and can have a severe effect on the results, so don't think it will not matter. Also, it is not related to Plaxis but applicable to all FEM/FDM programs. There are A LOT of discussions about this issue. Therefore, I recommend you to start from somewhere on the issue. I recommend two theses for you to get started. You can continue from their references after that.
Diplomarbeit (tugraz.at)
https://www.igs.uni-stuttgart.de/dokumente/Mitteilungen/54_Moeller.pdf
Dear Berk
tanx for your attention.
i'm intrested in calculation beta value for open face exavation...i read the attached thesis... betavalue was optained via camparing 2D and 3D modeling...i want a procedure to have beta value via 2D FEM modeling.
OK, I have tried to help. You have to investigate the issue in the literature. I can't tell you to take 50% since you may use it in a real project. No one in this forum can. Therefore, don't expect a direct answer.
tanx by the way....
i know practical value (value of 0.5 you mentioned)...as i know they model in 2 different phase...in one just excavation is activated without structure and in another one both are activated...after that you have settlement curves and with that you could calculate beta values.curves names are GRC (ground response curve) and SRC(structure response curve).
Dear Ahmad,
Calculating the beta value is an engineering process and therefore we cannot assist. This requires combining knowledge on tunnelling (as Berk correctly spotted) and information about your project.
I would also recommend you starting with literature, set up a simple model, test it and then move forward.