I am using ISA+HP model in my research and I have encountered some problem when looking into cyclic triaxial test for single element.
The target model was selected from Professor Wichtmann lab test ( TCUI11). This sample is a cyclic test for Karlsruhe fine sand. Also, for sand modelling the ISA+HP model was used (Fuentes, W., Wichtmann, T., Gil, M., & Lascarro, C. (2020). ISA-Hypoplasticity accounting for cyclic mobility effects for liquefaction analysis. Acta Geotechnica, 15(6), 1513-1531.).
Confining pressure is equal 200KPa and deviatoric stress was considered base on sinusoidal loading with Amp=40KPa (100 cycle).
The result of E22 is not desirable and in the curve E22 versus q no loop is observed.
Could you please tell me what is the main wrong in this simulation?