What are Linked load groups?
Linking load groups is a method to reduce the amount of combinations.
Consider 3 load groups: self-weight (SW), dead loads (D) and life load (L). According to EN 1990-1-1 equ. 6.10 the following 8 ULS FC combinations apply:
| 1,35 SW + 1,35 D + 1,5 L 1,35 SW + 1,00 D + 1,5 L 1,00 SW + 1,35 D + 1,5 L 1,00 SW + 1,00 D + 1,5 L | 1,35 SW + 1,35 D + 0,0 L 1,35 SW + 1,00 D + 0,0 L 1,00 SW + 1,35 D + 0,0 L 1,00 SW + 1,00 D + 0,0 L |
If all load groups have the same sence and direction, the maximum internal forces are found in the first combination and minimum internal forces in the last combination. All other combinations will give internal forces between the minimum and the maximum. Only the maximum and minimum internal forces are interesting during design.
1,35 SW + 1,35 D + 1,5 L → maximum internal forces
1,00 SW + 1,00 D + 0,0 L → minimum internal forces
If you link Self-weight with Dead loads and Life load, only the two combinations above will be generated. Resulting in less calculation time.
How to define Linked load groups?
- Go to
. - Select the groups you would like to link while holding the CTRL-key down. Click on
to link the selected load groups.
- An overview of the linked load groups can be requested using the button
.
- Click on
to remove all links between the load groups.
Which load groups may be linked?
Load groups may only be linked if their sence and direction are the same! Some examples:
- self-weight ↓ + dead loads 1 ↓ + dead loads 2 ↓ + live load A ↓ is OK, because they’re all vertical downward.
- self-weight ↓ + dead loads ↓ + snow loads ↓ is OK, because they’re all vertical downward.
- dead loads ↓ + wind loads →, is NOT OK
- dead loads ↓ + water pressure → ↑, is NOT OK
- dead loads ↓ + seismic (acts in multiple directions simultaneously), is NOT OK
- dead loads ↓ + fire, is NOT OK
