I used this UDF alot to return only the date part. I got from some site. It is also possible to get the time part mathematically. I just forget the URL though!

CREATE FUNCTION fn_Date (

@ADate datetime )

RETURNS datetime AS 

BEGIN

 declare @DateVal datetime

 set @DateVal = CAST(FLOOR(CAST(@ADate AS float)) AS datetime)

 return @DateVal

END