Test results show that : ( 1 ) the amount of creep deformation during monotonic primary loading depends on strain rate before creep , creep stress level , and creep time ; ( 2 ) during monotonic primary loading , the stiffness increasing magnificently shortly after creep ; ( 3 ) the direction of creep will change from positive creep ; to neutral creep and negative creep during unloading , while during reloading , it will change from negative , to neutral and positive creep
