Hi All,

I'm running a buried model pipeline stress analysis (1500#, 90 deg Temperature, Carbon steel, 16in, 24 mm WT, Water service).

As per project drawings, we have an isolation joint pit. I am modelling it as Above Ground (i.e. soil model 0 for the IJ pit). So we have buried pipeline upstream and downstream the IJ pit and the pit is AG.

As we need to check the loads on IJ, I'm modelling C-Node Anchors at both ends of the IJ.

The results I'm getting are terrible, huge axial loads (over 5000 kN). I was not expecting such high loads as C-Node Anchor should not act like a real anchor but as a dummy anchor.

I also did a run with a real anchor (i.e. no C-Node) and I'm getting much lower loads (one order of magnitude less)!

Also, checking the axial loads in any buried pipeline node, values are ok, far away from those 5000kN.

Something is wrong and I can't explain.

Any ideas? I'm sharing a snapshot for easy understanding (http://postimg.org/image/tczh4phvb/)

Thanks in advance

The CNODE anchors aren't acting as anchors. Your soil is acting like an anchor on both ends.

Your system is incredibly rigid.

I would personally treat everything inside the box as a closed, pre-engineered system and just focus on what's happening outside the box.

If you're responsible for engineering what's going on inside the box, then CAESAR is perhaps 75% of the solution you need.