The global axis system, (X, Y, Z), which is the reference for the group geometry is located in the start point of the first wall in the group meaning that first wall in the group has a least one node with (0,0) coordinates.
Global axis system position
The local axis system of the wall, (X, Y, Z), has X axis direction along the wall length and Y axis direction along wall height. The direction of X axis is from wall start point towards the wall end point.
Local axis system position
External loads and resultant forces on each wall are defined having as reference the local axis system. The group resultant forces are defined having as reference the global axis system:
- External vertical loads
Defining vertical loads with positive value means compression.
- Resultant forces on each wall
Wall resultant forces
1.N is the axial force
- N_{ } > 0 means compression
- N < 0 means tension
2.Vx is shear force
- V_{x}_{ } > 0 when it has same sense as x axis
3.Mz and Mx are bending moments; Mz is bending moment in wall plane and Mx is bending moment perpendicular on wall plane (out-of-plane)
- M_{z} > 0 means that using the right-hand rule, the versor of the moment has same direction as z axis
- M_{x }_{ }> 0 means that using the right-hand rule, the versor of the moment has same direction as x axis
Using right-hand rule: "grab" the axis and start to rotate the hand. If the thumb is oriented as the axis, the moment is positive. Otherwise it is negative.
Right-hand rule
- Resultant forces on the group of walls
Group resultant forces
1.N is the axial force
- N_{ } > 0 means compression
- N < 0 means tension
2.MX and MY are bending moments;
- MX > 0 means that using the right-hand rule, the versor of the moment has same direction as X axis
- MY _{ }> 0 means that using the right-hand rule, the versor of the moment has same direction as Y axis
Resultant forces having as reference the global axis system (X,Y,Z)
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