Transact SQL :: Add Random Dates To Existing Table From Defined Range

I'm trying to add random dates to date column in existing table, but these need to be week days (Mon-Fri).I'm a beginner in TSQL, worked with MS Access many years - in Access I used to do something a bit different:

DateAdd("d",(Int((5*Rnd([ID]))+1)),#31/08/2015#)
Table had ID, I gave a date it would start from (31/08/2015) and then range of ID to apply new date:
UPDATE table1 SET table1 .date = DateAdd("d",(Int((5*Rnd([ID]))+1)),#31/08/2015#)
WHERE (((table1 .ID) Between 1 And 5456));

This was applying random dates in range of 31/08/2015 + 5 days, so I could give a starting date of Sunday to get random dates populated over given IDs from Monday to Friday.Now, how can I do it in TSQL?I have a table with ID and dates column. I would like to apply new random dates from some range, but making sure they will be week days.