Yes, you say 'as was expected', 'as follows' or 'as is well known' - not 'as it was expected' or 'as it follows' or 'as it is well known'.
You shouldn't add the pronoun 'it' after the 'as', because 'as' acts as the subject - you don't need another subject 'it'. For example, you can say 'Expector will add another comment on the blog today, as happened yesterday."
The word 'as' can also act as an objective or complement, for example, "MyEC members keep writing blogs, as they did last year."
In addit