Starting based on my previous answer, which explained why:
Why can't I keep the pressure up?
The Bunker is like a firewall, it will work until the virus takes it down.
Some opponents will scout and be smart enough to prevent you from throwing down the bunker by scouting for your incoming SCV and deny him from finishing the bunker. Or deny the marines from getting inside the bunker. With the bunker and marines you damaged his worker and army, forced zerglings and delayed him... Nothing more!
But I want to deny his expansion.
Because in theory, that could make me win the game...
BUT. You can't, let me quote IvoFlipse:
The problem with a Zerg going for a Fast Expand is that a Hatchery
is also his Barracks, Factory and Starport all mixed into one building.
It would be unbalanced if you were able to deny Zerg from getting additional production.
The Bunker Rush is less effective if your opponent scouts it and uses enough micro...
See Donblas A for other alternatives, or give up and transition into Hellions or Medivacs or Banshees.
Let's look at it from the other side!
Because you can think the way your opponent does.
Terran can create an extra CC in his main and then go and drop it at his natural, Zerg can only prevent CC from being dropped there by placing Zerglings at his natural which the Terran has to build something against in order to remove the Zerglings so he can land. With the Zerglings he forces and damages Marines, also resulting in the FE to be delayed... Nothing more!
And yes, he has alternatives: Deny you from gas by placing Extractors in your main, go Mutalisks, ...
Because theory crafting could result in succes...
We had a conversation about this based on your questions, and came up with the following idea:
- Produce 6 Marines, 3 Hellions and 2 Medivacs.
- Run the 6 Marines towards your enemy exposition.
- Slightly after, drop Hellions into his Mineral line at his base, focus on Queen and Workers.
- Heal and pick up up units once they get heavily damaged and retreat to protect your natural.
While in theory you can pull this off, it is once again based on how well you both micro.