CSI Analysis Reference Manual
The following two specifications are equivalent:
(a) local=12, plveca=0, plvecb=100
(b) local=13, plveca=101, plvecb=102
Plane 1-2
Vp (a)
Axis 1
100
Axis 2
Joint j
Z
Vp (b)
102
Joint i
101
Plane 1-3
Axis 3
Y
X
Figure 17
Using Joints to Define the Frame Element Local Coordinate System
• If the reference vector is parallel to the 1-3 plane, then:
V2 = V p ´ V1 and
V3 = V1 ´ V2
In the common case where the reference vector is perpendicular to axis V1 , the
transverse axis in the selected plane will be equal to V p .
Section Properties
A Frame Section is a set of material and geometric properties that describe the
cross-section of one or more Frame elements. Sections are defined independently
of the Frame elements, and are assigned to the elements.
Section properties are of two basic types:
• Prismatic — all properties are constant along the full element length
• Non-prismatic — the properties may vary along the element length
98
Section Properties