Traditionally, structural fire protection is prescribed for structures after they have been optimized for ambient design loads (i.e., gravity, wind, seismic, and others). This century-old prescriptive framework endeavors to reduce the heating of individual structural components with the intent of mitigating the risk of structural failure under fire exposure. Accordingly, the vulnerability of buildings to structural failure from uncontrolled fire varies across different jurisdictions -which have differing structural design requirements for ambient loads- and as a function of building system and component configuration.
The ASCE/SEI 7 standard now permits designers to utilize performance-based structural fire engineering as an alternative to the code-default prescriptive method (standard fire resistance design). Specifically, Section 1.3.7 states that structural fire protection shall be provided per prescriptive requirements of the applicable building code, or by employing a performance-based approach in accordance with the new Appendix E section per building authority approval. Effectively, Appendix E brings structural engineers into the fold of structural fire protection design when alternatives to the prescriptive method are sought by project stakeholders. ASCE/SEI has also recently released the new ASCE/SEI Manual of Practice No. 138 (Structural Fire Engineering), which provides added guidance in support of ASCE/SEI 7-16.
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