Radial influence from drilled pier (caisson) 1

[hopetolearn]

I have a project where there are existing utility vaults and basements within a distance 1 to 2 times the diameter of proposed caissons. How do I calculate the surcharge on the existing features from the proposed caissons? Any help would be highly appreciated.

 

[hopetolearn]

I should add that the caissons are laterally loaded. Thanks

 

[miecz]

Here's one approach. Analyze the drilled shaft with a program that gives soil reactions, such as LPILE or COM624, as though the vaults didn't exist. Then re-analyze, cranking up the stiffness of the soil in the vicinity of the vault. Take your worst case soil reactions and apply them as a vertical line load to the side of your vault. You'll need to judge the width of wall that contributes in resisting the additional line load.