Hello Chua,
Thank you for your response.
You cannot delete superelevation strings as generally we prefer to apply superelevation to the carriageways strings. You can run again superelevation wizard on which you will received message as shown below, you need to click ok.
In addition to this, you can delete strings by using option, modify> edit Strings> delete String, here you need to select your design model and select string which you would prefer to delete.
Regards,
Purva Lakde