SR33 Fire engineering design of reinforced and prestressed concrete elements (2007)

Advances in knowledge relating to fire engineering design of concrete structures have led to the development of rational design methods as an alternative for time-consuming and expensive full-scale fire testing or the use of simple tabulated forms of fire resistance data.

Rational design methods are also better able to accommodate the effects of continuity and restraint, and the location of reinforcing or prestressing steel can be optimised, particularly for prestressed construction where prestressing steel rapidly loses strength at high temperatures and elements tend to be more slender.

However, rational design methods are unlikely to be warranted where the required fire resistance is less than about 2 hours for reinforced concrete and about 1 hour for precast prestressed concrete.

This report summarises the existing state of knowledge and discusses possible design procedures ranging from selecting an appropriate design fire to predicting the thermal and structural response of the member. Recommendations are also made supporting a review of existing New Zealand tabular forms of fire resistance data contained in MP9 for designing concrete structural elements.