Z662 and B31.8 both reference a 700 kPa/690 kpa (100 psi) pressure test delineation. Above this threshold strength testing is required while if below this threshold only a leak test is sufficient. I am wondering where did this threshold come from ?
I would really appreciate if someone could please shed light on what exactly does "effective soil unit weight" mean for soil spring calculations in Annex B of ALA Guidlines for Buried Steel Pipe. Also, why does the Annex B vertical bearing capacity equation has two separate unit weights...
We are doing stability analysis of buried pipelines using the chapter 10(underground pipelines) of Troitsky's tubular steel structures- theory and design book. I was wondering if this is a popular analysis in the onshore pipeline industry? Thanks.
As per the Palmer paper (link below) following is the equation for the required downward force w to avoid upheaval buckling:
w [1.16 - 4.76 (EI*Wo/cS )^(1/2)/P]P( cS*Wo/EI)^(1/2)
where
Wo is the installation submerged weight;
EI is the flexural rigidity;
cS is the imperfection height;
P...
k so here it is:
We have a buoyant section of pipeline where we are putting screw anchors. We have been asked to also consider local membrane (contact) stresses due to the presence of the screw anchor (anchor) on the pipe. For analysis this is what I did:
1) Calculated hoop stress (Sh)
2)...
