_{ }**Vertical Line Objects.** For vertical line objects the local axes have the following default orientation:

**Local axis 1** is along the line object. The positive local 1 axis is in the same direction as the positive global Z-axis, upward.
**Local axis 2** is perpendicular to the line object. The projection of the positive local 2 axis onto the global X-axis is in the same direction as the positive global X-axis.
**Local axis 3** is perpendicular to the line object. The direction of the positive local 3 axis is determined from applying the right-hand rule using the directions of the 1 and 2 axes described in the preceding bullets.

**Horizontal Line Objects**. For horizontal line objects (parallel to the global X-Y plane), the local axes have the following default orientation:

**Local axis 1** is along the line object. The projection of the positive local 1 axis onto the global X-axis is in the same direction as the positive global X-axis. If the line object is parallel to the global Y-axis such that there is no projection onto the global X-axis, the positive direction of the local 1 axis is the same as the direction of the positive global Y-axis.
**Local axis 2** is perpendicular to the line object. The positive local 2 axis points in the same direction as the global Z-axis, upward.
**Local axis 3** is perpendicular to the line object and is horizontal. The direction of the positive local 3 axis is determined from applying the right-hand rule using the directions of the 1 and 2 axes described in the preceding bullets.

**Other (neither vertical nor horizontal) Line Objects.** For line objects that are not vertical and are not horizontal, the local axes have the following default orientation:

**Local axis 1** is along the line object. The positive local 1 axis has an upward sense. The projection of the positive local 1 axis onto the global Z-axis is in the same direction as the positive global Z-axis, upward.
**Local axis 2** is perpendicular to the line object. The local 1-2 plane is vertical. The positive local 2 axis has an upward sense. The projection of the positive local 2 axis onto the global Z-axis is in the same direction as the positive global Z-axis, upward.
**Local axis 3** is perpendicular to the line object and is horizontal. The direction of the positive local 3 axis is determined from applying the right-hand rule using the directions of the 1 and 2 axes described in the preceding bullets.

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Thanks a lot. I´m just starting in the design of structures and this was very very helpful.

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So, for a wall element the is parallel to the global x-axis, M22 is the out of plane moment. But when your wall is perpendicular to the global x axis, M22 is the in-plane wall moment??

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M22 is based on local axis therefore it doesnt matter where is your global axis, M22 will always be out of plane moment.

Thanks.

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Hi Zstructures. I used SAP2000, and now I have started to use ETABS. In SAP2000, I could rotate a frame local axis with reference to two joints, but in ETABS I don’t know how do it. Please I need your help. Thanks.

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You should Provide an example with picture

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