5.1 These test methods are intended to provide a basis for evaluating the time period during which a beam, girder, column, or similar structural assembly, or a nonbearing wall, will continue to perform its intended function when subjected to a controlled, standardized fire exposure.
5.1.1 In particular, the selected standard exposure condition simulates the condition of total continuous engulfment of a member or assembly in the luminous flame (fire plume) area of a large free-burning-fluid-hydrocarbon pool fire. The standard fire exposure is basically defined in terms of the total flux incident on the test specimen together with appropriate temperature conditions. Quantitative measurements of the thermal exposure (total heat flux) are required during both furnace calibration and actual testing.
5.1.2 It is recognized that the thermodynamic properties of free-burning, hydrocarbon fluid pool fires have not been completely characterized and are variable depending on the size of the fire, the fuel, environmental factors (such as wind conditions), the physical relationship of the structural member to the exposing fire, and other factors. As a result, the exposure specified in these test methods is not necessarily representative of all the conditions that exist in large hydrocarbon pool fires. The specified standard exposure is based upon the best available information and testing technology. It provides a basis for comparing the relative performance of different assemblies under controlled conditions.
5.1.3 Any variation to construction or conditions (that is, size, method of assembly, and materials) from that of the tested assembly is capable of substantially changing the performance characteristics of the assembly.
5.2 Separate procedures are specified for testing column specimens with and without an applied superimposed load.
5.2.1 The procedures for testing loaded columns stipulate that the load shall be applied axially. The applied load is to be the maximum load condition allowed under nationally recognized structural design criteria unless limited design criteria are specified and a corresponding reduced load applied.
5.2.2 The procedure for testing unloaded steel column specimens includes temperature limits. These limits are intended to define the temperature above which a steel column with an axially applied design allowable load would fail structurally.
5.2.3 The procedure for unloaded specimens also provides for the testing of other than steel columns provided that appropriate acceptance criteria have been established.
5.3 Separate procedures are also specified for testing beam assemblies with and without an applied superimposed load.
5.3.1 The procedure for testing loaded specimens stipulates that the beam shall be simply supported. Application of restraint against longitudinal thermal expansion depends on the intended use, as specified by the customer. The applied load is intended to be the allowable desig......