How to get gtao effect for transparent object

[kong2dog]

here is the effect I want, I need aomap effect for the floor inside the transparent building, but when I use gtao, the aomap is always wrong, I can’t calculate the ao effect inside the building shell.
Is there a way to achieve this kind of effect, I want to ao to be inside the building shell.

[kong2dog]

this is the origin mesh, does anybody know how to achieve this effect. any way, not only ao, does anybody know any methods?