In the AISC Specification, serviceability refers to the condition in which a building’s functionality, appearance, maintainability, durability, and occupant comfort remain acceptable under normal use. Modern steel design is based on a limit-states philosophy, which recognizes two main categories: strength limit states (life-safety and stability, which must be satisfied) and serviceability limit states (functional performance, which should be satisfied) [1].

Unlike strength requirements, serviceability limits are often not codified because acceptable limits vary by building type and usage and depend on the expectations of the owner and occupants. For this reason, serviceability requirements are commonly treated as project-specific performance criteria, typically defined through contractual agreement and coordination with the owner (or the owner’s representative) [1].

Accordingly, MkaPEB allows the user to define project-specific serviceability limits and evaluates serviceability using the ASCE 7-22 Allowable Stress Design (ASD) load combinations [2], as follows:

  1. D
  2. D+L
  3. D+(Lr or S or R)
  4. D+0.75L+0.75(Lr or S or R)
  5. D+0.6W
  6. D+0.75L+0.75(0.6W)+0.75(Lr or S or R)
  7. 0.6D+0.6W
  8. D+0.7Ev+0.7Eh
  9. D+0.525Ev+0.525Eh+0.75L+0.75S
  10. 0.6D-0.7Ev+0.7Eh


References:

[1] West M, Fisher J. AISC Design Guide 03 – Serviceability Design Considerations For Steel Buildings. 2nd ed. Chicago (IL): American Institute of Steel Construction; 2003.

[2] American Society of Civil Engineers. "Minimum design loads and associated criteria for buildings and other structures." American Society of Civil Engineers, 2022.