3 inch pvc in concrete
It is not ideal but you can bury it in concrete.  If you have enough room you can use what is called a repair coupling.  It is a coupling with no stop in the center.  Slide the repair coupling on the longest accessible side.  You would glue a 2" stub in the end of the Tee facing the repair coupling, mark the pipe in the floor with your Tee set up, and cut it on your mark.  Glue the Tee on the opposite side of the stub and slide and glue the repair coupling over where you cut the existing pipe up to the Tee.