Sewer pipe in creek bed - Design Criteria

[cbailey82]

Where can i find what forces (design criteria) are supposed to be used to design sewer pipe supports when the concrete pier pipe support and its foundation are located adjacent to a creek ... eg. water forces, debris forces, buoyancy, etc?

 

[WARose]

Hey Colin, long time no see.

I am not aware of such a criteria. The best thing to do is to stay aerial (i.e. out of it). About the closest thing to it is: AASHTO (17th ed.) does have some load calculation methods for "Dynamic Ice Force" against piers in a stream. (They just cover debris by saying it should be considered. And they give a flow pressure that takes into account debris, but not sure if this includes a impact force.)

I'd check with your local code official where this is going by the way. They've jumped on me for too many crossings in the air.....in the body of water itself gets them real antsy.

 

[BridgeSmith]

Any Edition of either of the AASHTO specs (Standard or LRFD) will include how to calculate stream forces, and estimate debris loads, ice loads, etc. I would suggest avoiding the the first 3 LRFD editions, though, due to the many errors and cumbersome organization of the provisions.