In shaft, Elastic supports are defined in panel thickness definitions. In addition high nodal vertical stiffness is provided at bottom of the shaft. All Local Z axis of panels are directed towards outer face of panels. When uniform effective pressure applied from outside, the deformation of shaft moving outwards at top portions as attached in picture below. How to avoid such deformations or correct the model. (model is attached)
Unusual Deformation pattern on top portion of Shaft due to uniform lateral loadings
In shaft, Elastic supports are defined in panel thickness definitions. In addition high nodal vertical stiffness is provided at bottom of the shaft. All Local Z axis of panels are directed towards outer face of panels. When uniform effective pressure applied from outside, the deformation of shaft moving outwards at top portions as attached in picture below. How to avoid such deformations or correct the model? (model is attached ) 
Are you sure about the earth pressure?
It should be triangular (like below) with a maximum pressure about 130 kPa at the bottom level
M. Agayr
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max SLS deformation 5 mm
M. Agayr
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Sorry, forgot to change surcharge load sign.
Modifications made to the model:
- Z local axis pointing toward the cylinder center
- Uz + uplift for all Thickness
- Earth density 18 kN/m² and k=0.33
Max SLS deformation is now 28 mm
M. Agayr
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yes.. Earth pressure values are given by Plaxis inputs and agreed with Geotech team. They vary along the height of shaft. 
