Section 72 of 102
71. Capacity and Demand
Stable section ID: S05-CON-007-SECTION-72 · 50 content blocks
Capacity represents the verified ability of an Entity or system to resist, transfer, supply, receive, or tolerate an engineering action.
Demand represents the action or performance required from that Entity under a defined condition.
A Capacity declaration shall define:
subject;
capacity type;
value or envelope;
direction;
applicable state;
limit state;
duration;
environmental conditions;
degradation condition;
source;
evidence;
uncertainty.
A Demand declaration shall define:
subject;
demand type;
value;
load case or operating scenario;
analysis source;
configuration;
timestamp where operational;
uncertainty.
Example:
capacity Node_N01_Capacity {
subject: @Node_N01;
limit_state: ultimate;
- axial_compression: certified(
- 180 kN,
- evidence: @Node_Type_Test_03
);
- shear_x: certified(
- 42 kN,
- evidence: @Node_Type_Test_04
);
}
demand Node_N01_Demand {
subject: @Node_N01;
source: @Structural_Analysis_Rev03;
load_combination: @ULS_Combination_01;
axial_compression: 92 kN;
shear_x: 18 kN;
}
Capacity–demand evaluation shall account for combined actions where interaction exists:
- require interaction_check(
- capacity: @Node_N01_Capacity,
- demand: @Node_N01_Demand
) <= 1.0;
The lowest applicable capacity from Type certification, specific Instance condition, Interface limits, Profile limits, and current degradation shall govern.