American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

Alternative Title

Research Report RP22-02


Performance-based design for fire conditions has been increasingly adopted for different structural systems over the last decade. The objective of this project is to exemplify through a case study how the newly proposed Appendix 4 to AISI S100 [1] on ‘Structural Design for Fire Conditions’ could be used by the metal building industry. The scope of work on the project includes the following:

(1) Identification of a prototype metal building to serve as an exemplar case study for the structural fire design procedure.

(2) Definition of the performance objectives and design requirements for the building in the fire situation. This includes the determination of the applied loading based on load combinations relevant to the fire situation.

(3) Determination of a set of design-basis fires. The design-basis fires are based on the physical characteristics of the compartment, fuel, and ventilation conditions. The ASTM E119 [2] standard fire is also considered.

(4) Determination of the temperature distributions in the members of the building structure based on heat transfer analyses. Finite element thermal analyses of the section of the members are conducted taking into account the thermal exposures generated by the design-basis fires and the temperature-dependent thermal properties of the materials.

(5) Determination of the structural response and strength of the metal building structure in the fire situation. The Direct Strength Method (DSM) of the AISI S100 [1] design standard is used to calculate the capacity of the structure considering the reduction of mechanical properties due to temperature. Finite element analyses of the structure are also conducted, taking into account large displacements and effects of temperature, to compare the results of a numerical analysis method with those of the DSM.

(6) Verification that the design meets the performance objectives in the fire situation.

(7) Characterization of the fire rating of UL-assemblies using heat transfer analysis and the prescriptive limiting steel temperature criteria. This serves to compare the outcomes of the analysis method with the physical testing qualifications, as well as to analyze assemblies that are currently not rated by UL.

(8) Summary of the work and findings.


American Iron and Steel Institute (AISI)

Publication Date

May 2022

Document Version

Final Version


© 2022 American Iron and Steel Institute, All rights reserved.


Prepared for the American Iron and Steel Institute (AISI) and the Metal Building Manufacturers Association (MBMA)

Project start date: 01 July 2021
Project end date: 31 October 2021

Document Type

Technical Report

File Type




Technical Report Number

AISI RP22-02