I am currently modelling a test conducted in the geotechnical centrifuge facility at HKUST. The test consisted of a sand slope with a rising water table. The slope height in prototype scale is 20 m. The material used was Leighton Buzzard sand (Fraction E). In the test the water started infiltrating into the slope from the back of the slope. No water drainage was permitted downstream of the slope.
I am trying to model the centrifuge test using the user defined hypoplastic model for sand. When I run the model the stresses are consistent with some hand calculations I have done (p’, q, water pressures, etc.). However, I am having problems with two things.
1. Small displacements. The displacements I get are very small (only a couple of millimetres).
2. The factor of safety (FS) is extremely large. It seems as if the FS keeps increasing indefinitely for my model.
I have used different material parameters that I have obtained from literature but I am still having the same problem (i.e. https://doi.org/10.1139/cgj-2012-0445).
Please find attached some of the results of my model.
Any suggestions would be appreciated.