Approach Slab on Unground Garage

[ron9876]

I am a building guy designing a section of a parking garage that extends beneath a street. Actually it is about 60' wide tunnel with 4'-5' of soil on top that connects two larger unground garages. The street has asphalt pavement.

My question is do I need approach slabs?

 

[hokie66]

Yes, unless you want a big bump. The soil adjacent to the tunnel will settle, no matter how hard you try to prevent it.