Example
Example for Envelopes
Let’s assume a continuous beam of two spans. The beam is subject to load sorted into five load cases.
LC1 – permanent – self weight, distributed load in both spans
LC2 – variable – distributed load in the left span, load group G1
LC3 – variable – distributed load in the right span, load group G1
LC4 – variable – crane, concentrated force in the middle of the left span, load group G2
LC5 – variable – crane, concentrated force in the middle of the right span, load group G2
The variable load cases are divided into two groups:
G1 – imposed floor load, standard group
G2 – crane, exclusive group, only one of the load cases may be acting at the same time
The user defines the following envelopes:
LC1 + 1.2*LC2 + 1.2*LC3 +1.3*LC4 + 1.3*LC5
The program will then generate (explode) the following linear combinations:
LC1
LC1 + 1.2*LC2
LC1 + 1.2*LC3
LC1 + 1.3*LC4
LC1 + 1.3*LC5
LC1 + 1.2*LC2 + 1.2*LC3
LC1 + 1.2*LC2 + 1.3*LC4
LC1 + 1.2*LC2 + 1.3*LC5
LC1 + 1.2*LC3 + 1.3*LC4
LC1 + 1.2*LC3 + 1.3*LC5
LC1 + 1.2*LC2 + 1.2*LC3 + 1.3*LC4
LC1 + 1.2*LC2 + 1.2*LC3 + 1.3*LC5
Example for Code-related combination
Let’s assume a continuous beam subject to several loads.
LC1 |
self weight |
V1 |
|
V2 |
|
V3 |
|
V4 |
|
S1 |
|
S2 |
Let’s define a code-related combination to Eurocode. The combination definition contains all the defined load cases.
Name |
Type |
Load cases |
Coefficiens |
UEC |
EC – ultimate |
LC1 V1 V2 V3 V4 S2 S2 |
1.00 1.00 1.00 1.00 1.00 1.00 1.00 |
SCIA Engineer creates a set of "dangerous" combinations for the given definition:
UEC.1 |
User – ultimate |
LC1 |
1,35 |
UEC.2 |
User – ultimate |
LC1 V1 V2 V3 V4 |
1,35 1,50 1,50 1,50 1,50 |
UEC.3 |
User – ultimate |
LC1 V1 V2 V3 V4 |
1,00 1,50 1,50 1,50 1,50 |
UEC.4 |
User – ultimate |
LC1 S1 S2 |
1,35 1,50 1,50 |
UEC.5 |
User – ultimate |
LC1 S1 S2 |
1,00 1,50 1,50 |
UEC.6 |
User – ultimate |
LC1 V1 V2 V3 V4 S2 S2 |
1.35 1.35 1.35 1.35 1.35 1.35 1.35 |
UEC.7 |
User – ultimate |
LC1 V1 V2 V3 V4 S2 S2 |
1.00 1.35 1.35 1.35 1.35 1.35 1.35 |
When displayed in the Document, the Combinations table looks like: