JonnyD1980
Structural
- Feb 18, 2015
- 1
Guys,
Was looking for a bit of advice on net pressures for structural design, when moments and shear have been derived directly from a FE model.
I am looking at a large foundation for a eccentrically loaded structure. I have modelled it as a 2D plate on Robot 2015 with non-linear springs.
The model is constructed as a plate with weight of the concrete, soil overburden and super structure forces.
When designing traditional shallow foundations by hand, we would calculate the gross pressure on the underside of the foundation and then subtract the weight of the excavated soil above the new formation to get a net pressure which we use to calculate shears and moments.
When flying FE, I am guessing that the moments and shear derived by the programme are based on gross pressures? As the model don't know that its supposed to be buried!
Any thoughts on how to handle net pressures when using FE? Do I have to subtract a net moment from the derived FE model to get a representative moment (or shears)?
Any thoughts advice would be appreciated.
Was looking for a bit of advice on net pressures for structural design, when moments and shear have been derived directly from a FE model.
I am looking at a large foundation for a eccentrically loaded structure. I have modelled it as a 2D plate on Robot 2015 with non-linear springs.
The model is constructed as a plate with weight of the concrete, soil overburden and super structure forces.
When designing traditional shallow foundations by hand, we would calculate the gross pressure on the underside of the foundation and then subtract the weight of the excavated soil above the new formation to get a net pressure which we use to calculate shears and moments.
When flying FE, I am guessing that the moments and shear derived by the programme are based on gross pressures? As the model don't know that its supposed to be buried!
Any thoughts on how to handle net pressures when using FE? Do I have to subtract a net moment from the derived FE model to get a representative moment (or shears)?
Any thoughts advice would be appreciated.
