cyclic load

I am working on modelling ballast aggregates under triaxial loading. Confining pressure applied in the intermediate and minor principal direction and cyclic compression load applied in the major principal axis direction. I wanted to capture the continues plastic strain (PS) with cycles (N). My test results show that the PS increase with N up to about 10,000 cycles and the rate of strain slowly diminish for later cycles and almost stay constant after N=100,000. What available model in Abaqus can be used to get this behaviour. I have to run my analysis at least for 10,000 cycles.

Could you please anyone help me to input Direct Cyclic Periodic Pressure Load.

I have a sine load of amplitude 50 kPa and frequency 5 Hz (ang. freq 31.42 rad/s).

I need to ramp my load to 100 kPa for 5 seconds and then to run the sine load of above amplitude with its mean load on 100 kPa. The sine load go for 10 seconds.

I try with Direct cyclic periodic pressure, but when I check the pressure on applied surface, the pressure not seems what I am applying.