Dear all,

Forgive if this is a stupid question . How to determine load on support by using local element force instead of restrain report? please see node 20 which has restrain run in X global direction.

Is the load on support node 20 in X global 74 N? instead of 37 N, -287623 N or 287549 N?

I mean if we sum -287623 + 287549 = -74 N and 37+37 = 74 N. The same for Y and Z global. Please advice from FEM side.


CAESAR II LOCAL FORCE REPORT
CASE 2 (OPE) W+T1+P1
ELEMENT ------Forces( N.)------ -----Moments( N.m. )-----
NODES fx fy fz mx my mz
20 -287623. -3733. -1887. -10.3 -1818.8 15258.1
20 287549. -12220. -1864. 10.3 1818.8 -15258.1


CAESAR II RESTRAINT REPORT
CASE 2 (OPE) W+T1+P1
----Forces( N.)----- ----Moments( N.m. )----
NODE FX FY FZ MX MY MZ TYPE
20 37. -3751. 0. 0. 0. 0. Rigid +Y
20 37. 0. 15953. 0. 0. 0. Rigid GUI

Dear Manik,

1. You should add the loads from individual supports. You have 2 supports at node 20. You should better look at restraint summary report which will give you the resultant of all the support types acting at the node.

2. There is a sign difference between restraint summary and local element forces as the restraint summary shows you the loads imposed by piping on support and the local element forces show the support's reaction.

3. At times looking at the local element forces may be confusing as the XYZ of local elements is dependent on the orientation of that particular element. The x axis in local element report will be the axis of pipe at that node which need not match with your overall (global) coordinate system.

Regards
Siv

Dear Siv,

Thanks for your explaination. "restraint summary shows you the loads imposed by piping on support and the local element forces show the support's reaction" has opened my mind :))he..

I ask about this since I have pipe 1.8 km in length and run "not" in major global coordinate. And the allowable load on support available in local coordinate f vertical, f axial, and f lateral.

So now, I just need to sum the local force fx, fy, fz for nodes and compare to allowable.

Why CAESAR does not make one more report option, let say it as "Local Restrain Report" and also give the summation at nodes :)if has 2 support type there. So very easy to compare to allowable especially to those run not in major global coordinate.

Read the section on "Local Coordinates" in the Technical Reference Guide. Then you will understand why there is no local coordinate system for a restraint. (Now we could generate a set of restraint loads based on the local coordinate system of some element, but that would be very tedious for you to define - i.e. what is the local coordinate system to use for a restraint at the midpoint of a bend.)

Dear Manik,
Caesar does not give you restraint reports in local coordinates for the reasons expalined by Richard.
However your problem can be solved by rotating your model. Rotate the model so that the segment of piping which was not aligned with Global coordinates is now aligned. Check the restraint report for the concerned nodes. You may decide to rotate in such a manner that your pipe axis becomes X axis.
If you have various segments which are not aligned with Global coordinates you may have to do this rotation exercise several times. But that should not take much time.

Regards
Siv

Thanks Ricahrds, Siv,

Dear Siv,
I know to use the way you describe. For the pipe model which has so many nodes run in many VARIATION of directions, by rotate them, not all will fall in major global coordinate. But could be reduce.

Dear Richards,
I wish still there is the optional report for "local restrain report" with exception to node(s) where change in direction between 2 elements and has restrain on it. Report also include summation value of reaction there. Then easy to compare against the allowable load on support with type of model like I mentioned above.

For the node(s) mentioned above, Caesar just need to put *** for reaction. Then let the users to take a look themselves at that special location. It Looks like crazy idea :), sorry.