Modifying server mappath

I have a web-app that uploads files to a folder name "uploads" thats within the project folder on the server. This is my code.

fuUpload.SaveAs(Server.MapPath("~") + "\uploads\" + System.IO.Path.GetFileName(fuUpload.FileName))

It works just fine, but I need to save the path like this. "//web/appfolder/uploads/filename.txt"

How do I go about that?

Thanks,
...