I think you would have to model the problem using anisotropic material theory. Composite plate elements, in FEM, would be a good choice. You could use directly most of your test results to tune up the parameters of the model.
Using average stiffness and strength material values and an isotropic...
A DLF is used just to take approx. into account the dynamic response ("dynamic amplification") of a structure (piping system) to a given dynamic load, when the static (maximum) value of the load is applied to the structure and the system is solved statically. DLF may be defined as: "maximum...
As Taro said, you need an appropriate ground accelerogram suite, reflecting the seismologic conditions at the site, and the use of the building code rules to select and “scale” this accelerograms to the code requirements.
In the meanwhile, you can use existing recorded accelerograms to “build”...
Are you considering in your analysis rotational ("torsional") effects? They may cause a given wall get a "total shear" greater than its "direct shear" (base share distribuited between walls according their stiffnesses).
Perhaps it may be the cause of the difference you found out, specially on...
I agree with vonlueke in trying to avoid to suppress horizontal displacements of the nodes of the base plate applying unneccessary horizontal constraints. This could reduce the reported values of the tension membranal stresses in the base plate. And these stress values are important to check...
It is generally assumed that if a high tensile hydrostatic stress state is applied to a metallic material (steel), it will not yield but it will undergo a brittle failure. This is the reason to avoid “triaxial tensile stress states” in steel structures (joints, notches).
A steel ball submerged...
The statement “against permanent deformation” implies plastic deformation, i.e., yielding. Yielding, in ductile materials, results from shear stresses. Only von Mises criterion (shear deformation energy) and Max Shear criterion (maximum difference between principal stresses) are useful to...
NL FE Software can give you good results (Nastran SOL106). To obtain safe results, you have to analyze the kind of post-critical behaviour of the structure (stable or unstable). Non-planar shells may be unstable. In these cases, the nature and/or magnitude of the imperfection you have to...