How to evaluate when menopause happens in women who undergo total abdominal hysterectomy and bilateral salpingo-oophorectomy?

Not necessary. When your ovaries are removed you are in menopause. There is no reason to be evaluated any further to diagnose menopause.
Right away. Removal of both ovaries means a woman can no longer make cyclic hormones and she will go into immediate menopause. If she was making hormones before the surgery (premenopausal), she is likely to develop significant hot flashes, night sweats, and sleep changes within a week. This can be avoided with the use of post-operative estrogen.