Try MaxiBIM.
MaxiBIM Modelling Tools allows you to extract drawing lines from linked DWG files, and read the dimensions accordingly to create Revit Family. It is perfect for a situation like you are having here in which you have a concrete beam plan to be redrawn into Revit.
Watch This Demo of MaxiBIM AEC on YouTube and see if this suit your need.
* Notice this product is still in the beta stage, and you can only get it from www.maxibim.com for a beta-trial version.
