ABSTRACT
The design of concrete elements affected by exposure to re may be undertaken in one of two ways: a prescriptive approach or a calculation approach. The prescriptive approach, in which tables of minimum dimensions, minimum axis distance, and other parameters corresponding to a given standard re endurance are consulted, was covered in Chapter 3. It will not be discussed further except to note that even in the calculation approach minimum dimensions are conveniently determined using such tables when the exposure is taken as the standard furnace temperature-time curve. It should be noted that the minimum axis distance required for adequate re resistance for low periods of re resistance is likely to be less than that required for durability, and thus a calculation approach may not be viable.
