A New Design Approach for Steel Structures Exposed to Fires

Abstract

There is a need to develop an analytical methodology for the design of steel framed struc tures exposed to fire to provide design engineers with an approach which will achieve a known level of performance. An important step in this process is the development of a simple technique for determining the thermal impact of a fire.

Such a technique is presented in this paper for insulated steel structures. This approach involves a new technique to determine a post-flashover fire's time-temperature history. Based on this, a method is presented for determining the peak temperature in an exposed steel beam, as well as a means to determine an equivalent fire endurance rating based on the ASTM E119 Standard Fire Test. This work is an extension of the existing applications of the Normalized Heat Load Concept.

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