Culvert Design EH load

[Stewie_]

Hi, Dear All,

I have a quick question on culvert design EH load.
Geotech engineer gives EH values (equivalent fluid pressure) for active (40 pcf)/at-rest (60 pcf)/passive (480 pcf) earth pressure.
When model the culvert in Eriksson, for EH loads, I only entered in the active and at-rest values, but not the passive value.
I think it is because the possible culver failure pattern will not involve the side walls pushing into soil. Am I right on this?
Please advise.

Thanks~!

 

[HTURKAK]

If the side walls pushing into soil develops passive thrust ,probably this will be end of game meaning , you need to increase the wall thk. You are expected to use EHmax (60pcf) and EHmin ( 30 pcf ) with assumption of submerged soil con.

Pls look local code for design criteria and load combinations at your zone.

The following doc. is useful and there is a worked example.
Good luck ..



Use it up, wear it out;
Make it do, or do without.

NEW ENGLAND MAXIM

 

[BridgeSmith]

We typically use max at-rest pressure for design of the walls for positive moment (bending inward at midheight of wall) and for negative moment at the corners (when corners are reinforced to create a moment resisting connection). We typically use half the at-rest pressure on the walls as a minimum when designing the top and bottom slabs.