Concrete Damaged PLasticity - Effect of Kc

I'm trying to develop yield surface of a material for a particular value of hydrostatic stress(since CDP model uses drucker-prager hypothesis).. In user manual, it is given that, for Kc value of 1, i should get a circle, and for Kc value of 0.667, i should get a shape of inverted triangle in deviatoric plane.. But I have tested for 3 values of Kc, 0.667, 0.9 and 1, for all, i'm getting the same inverted triangle in the deviatoric plane. 

*Concrete Damaged Plasticity 
22., 0.33, 1.16, 0.667, 0. 

I wanted to know why is that.? Or am I missing something.? Or my interpretation is wrong.? 

Thanks in advance.