hello. gud morning to all.......sorry to ask this dumb question. im just new to caesar.

i did a stress analysis for a burried piping and here is the report;

RESTR REPORT: Loads on Restraints
CASE 1 (OPE) W+T1+P1

NODE Fx Fy Fz Resu.Force Mx My Mz Resu.Moment Restraint Type
lb lb lb lb ftlb ftlb ftlb ftlb

100 -1097 14 7254 737 0 0 0 0 Bi-linear X2
100 522 0 79 528 0 0 0 0 Bi-linear X2
100 0 0 0 0 0 0 0 0 Bi-linear X2

The questions are:
Why there are three nodes reflected in the reports. What are these forces?

I also noticed that the resultant forces are always positive eventhough there are negative forces.


Hope you could help me with this, many thanks.

Dear John,

Did you mean?

100 -1097 14 7254 737 0 0 0 0 Bi-linear X2
100 522 0 79 528 0 0 0 0 Bi-linear Y2
100 0 0 0 0 0 0 0 0 Bi-linear Z2

If yes, please note that "restrains report" list all reaction for every single type of restrain. you have three type of support in buried by soil regarding to your model. That's why you have three row report.

But "restrain summary report" list the reaction at node in one row and sum each direction X, Y, Z. Please try by using "restrain summary" in report options for comparison.

thaks for your quick reply.

But the restraint types are all "BI-LINEAR X2"

If the line is skewed, the restraints are defined with "direction cosines". A label is still necessary for output, and this defaults to the "X" direction.

Go back to the input for node 100 and review how the restraints are defined.

when i converted the original model into a burried piping model, all the restraints in the nodes were defined as X2

Dear John,

Please take a look to next element, sometimes the restrain of element 100 defined there. Let say in elements 99-100 and 100-101.

Is the format of restrain like?
X2 (.813733, 0, .58123821)
...
...

The restrain by soil are in x, y, z (local) coordinate of element if we see it in plot view. But the restrain report listed in global coordinate. The three row you mentioned are the reaction to global coordinate X, Y, Z from three type restrain.

actually my pipeline is skewed.

These are the Restraint type in my burried piping model after i converted it. (NODE 100-101)

X2 (-.14951, .001866, .988756)
X2 (-.98875, 0, -.1495202)
X2 (.000279, .999998, -.00184)


Many thanks.