Page 214 - Structural Steel Designers Handbook AISC, AASHTO, AISI, ASTM, and ASCE-07 Design Standards

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BUILDING CODES, LOADS, AND FIRE PROTECTION*

4.42 CHAPTER FOUR

FIGURE 4.13 (Continued)

is predicated on the assumption that test assemblies are “representative” of actual construction. In
reality, this assumption is extremely difficult to implement in laboratory-scale fire tests. The primary
difficulty arises from the size of available test furnaces, which typically can only accommodate floor
specimens in the range of 15 by 18 ft in area. As a result, a typical test assembly actually represents
a relatively small portion of a floor or roof structure. Thus, even though the standard fire test is fre-
quently described as “large scale,” it clearly is not “full scale.”
In the attempt to model real floor systems in a representative manner, several problems arise. For
example, since most floor slabs and roof decks are physically, if not structurally, continuous over
beams and girders, real beams and girders are usually much larger than can be accommodated in

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