Yes, a value of 0 indicates that the default value from the Code will be used. The EN 13480 code provides a minimum value of k=1 (in k*f-sub-f) for loads which act for more than 10% of any 24 hour period (other k's are 1.15, 1.2, 1.3 & 1.8). CAESAR II uses this k=1 as the default value.