5.3Joint and Member Labels and Numbers
Joints and members are automatically numbered and labeled as they are drawn or generated on the basis of first-input, first-numbered. Labels are assigned as the joint or member number and may not be changed in spCad.
Since the user does not have control over the joint and member labels, spCad has a Relabel option. It instructs the program to relabel joints and members in a predetermined systematic manner. Notice though that this option affects labels only and not joint and member numbers.
spCad searches for the joint with the lowest X, Y, Z coordinates in the entire model, and assigns label "1" to it. The program then increments the label by 1 and assigns it to the next joint moving in the positive X direction first, the positive Z direction second, and finally in the positive Y direction, until all joints are labeled (see Figure 5-10a).
•Start with the XZ plane with the lowest Y coordinate (plane Y0 in Figure 5-10b)
•In plane Y0, start with the members that are parallel to the X-axis (X-beams).
•Label "1" is assigned to the beam with the lowest (X, Z) coordinates for its start joint.
Figure 5-10 Relabeling joints and members
•Moving in the positive X direction first, then in the positive Z direction second, member labels are incremented by 1 until all the X-beams on plane Y0 are relabeled (see Figure 5-10c)
•Similar to the previous two steps, the Z beams are relabeled next, moving in the positive Z direction first, and then in the positive X direction until all the Z-beams on plane Y0 are relabeled (see Figure 5-10d)
•Moving up the positive Y axis to the next plane, the three preceding steps are repeated until all the X beams and Z beams on all the XZ planes are relabeled.
•Members parallel to the Y axis (columns) are relabeled next, starting at the bottom of the model and moving in the positive X direction first, the positive Z direction second, and in the positive Y direction last (see Figure 5-10e).
•Finally, diagonal members are done in a manner similar to the previous step