Utility line under an abutment footings

[Parkerlax]

I have a contractor constructing abutments for a temporal bridge and there appears to be utility lines running underneath the proposed location of the abutments. The abutment footings are about 10' wide and the existing utilities will be about 5' below the footings. I know this is an issue and was wondering what could be done. Would step footings work to divert the effective stresses? Please advice. Thank you

 

[Geostructsparks]

What sort of utilities (and if private utility, it will have its own rules) and what weight of abutment?

 

[Parkerlax]

The loading is HS20-44 Truck loading per AASTHO 2002. The utilities underneath are gas and communication cables

 

[Geostructsparks]

Assuming this is not high pressure gas, and is a new, flexible pipe, I don't suppose that putting a temporary footing would be a problem. Consider voiding under the footing (styrofoam, void forms) so that the stress is distributed less to the soil overlying the pipe. You really haven't said what the footing load is (Golden Gate bridge with HS20 loads, 40' span, will be a little different. Again, probably the utility companies will be a bigger obstacle than the technical solution. This will be in for 6 months or less?