Hello,
I am new to Caesar II and this Forum, so please bear with me if these are a silly questions or they have been answered before (my search didn't yield anything useful):

According to the CII documentation I have seen, restraint type are only positive. So:

1. Why does Caesar sometimes return negative restraint types in the return neutral file? What is their meaning?
2. How does Caesar interpret negative restraint types in the input neutral file?

Many thanks,

JN

You have 6 axes.

Global: X, Y, and Z.
Local: Axial, Lateral, and Vertical.

Negative restraints are simply restraints oriented in the negative direction. If +X is South, then -X is North. X indicates both North and South.

Edit to add:

Piping situated along the primary axis is the most common scenario. Therefore, X, Y, Z, +X, +Y, +Z, -X, -Y, and -Z can be substituted with LIM, GUI, +LIM, +GUI, -LIM, -GUI depending on the situation.

However, when your piping is at an arbitrary angle, X, Y, and Z definitions remain in the primary axes. It is generally better to use LIM and GUI variants. Alternatively, supports can be defined as X(#,#,#), +X(#,#,#), -X(#,#,#), where #,#,# is the unit vector of the support in question.

JN,

Here is the actual situation:

There are not "positive" and "negative" restraints in CII. They are actually UNI-DIRECTIONAL RESTRAINTS.

Assuming the most frequent case when Y is the upward vertical direction, +Y restraints is the most typical restraint: SIMPLE REST SUPPORT, meaning that Pipe Movement is ALLOWED ALONG POSITIVE DIRECTION OF "Y" axis and FORBIDDEN ALONG "Y" NEGATIVE DIRECTION.

Let's assume you want to define in a Node, a REST + HOLD-DOWN Restraint. In that case, you'll have in that Node 2 restraints:
+Y is the Rest Restraint (e.g. movement along "Y" downward direction is forbidden, while "Y" upward movement is allowed).
-Y / Gap 2.00 mm will be the Hold-Down Restraint with typical 2.00 gap, meaning that "Y" downward direction is formally allowed, while only maximum 2 mm "Y" upward movement is allowed.

Let's assume now that you want to define a lateral Guide along +/- X direction with 3 mm gap symmetrically distributed. You'll need to define X / Gap 3.00 restraint only.

BUT if you'd like a non-symmetrical Guide with 5 mm gap towards +X (X positive direction) and 10 mm gap towards -X (X negative direction), you'll need to define:
+X / 10.000 Gap
-X / 5.000 Gap.

Rotations' definition principle is similar, assuming that positive rotation means trigonometric sense (e.g. opposite to clock indicators sense) when you look from Axis Positive Edge towards negative direction.

My suggestion is to try in Caesar II model to define STEP-BY-STEP each individual restraint and to watch the graphical window update after each newly defined restraint. You'll understand "immediately" the Uni-Directional Restraint "philosophy" in Caesar II without any other sophisticated or high-level explanations.

Regards,

Perhaps I wasn't clear enough.

I am talking about the neutral file, where AFAIK there is no +Z or -Z for example, but floating point numbers.

For example, according to the documentation, a -Z direction should appear as 18.000 in the #$ RESTRANT section, but sometimes it comes back from CII as -18.000.

And to be clear, I am aware of what +/-[X|Y|Z] means. I need to know how to interpret the neutral file output when the node type is negative, as per the example above. Perhaps someone from Caesar Development can explain?

The best thing to do here is open a Support Request on Smart Support and send in the job file and the neutral file. This way you'll get a complete answer, without any guess work.

Thank you all who responded.