Building Design Predictions and Models

The main objective of ensuring safety in building design is to reduce the level of damage to the building and its contents and to minimize the loss of life in the event of an accident or natural hazard. To achieve this objective, buildings should be designed to have adequate resistance against accidental loads. In the design against accidental fire, the building should be able to withstand the fire for a reasonable time, and the fire should be contained within a localized part of the building. Several safety measures must be taken to meet the expected performance, including evacuating people from the building, detecting and suppressing the fire, stopping the fire from spreading, and protecting the load-bearing members from losing their strength at elevated temperatures. Existing test methods assess performance under a single, standard exposure that was developed when fuel characteristics were quite different from today. These tests do not provide insight into the interaction of assemblies that were tested independently nor to the sensitivity of the assembly to variations in construction to the design specification that was tested. The fire endurance concept has been successful in the prevention of fire-induced collapse by protecting structural elements for sufficient time so that manual or automatic suppression could occur. Spread of fire was also limited to a maximum area by rated firewalls with these maximum areas determined by what could reasonably be handled by fire fighting forces. Fire rated assemblies were used to protect means of egress for sufficient time to allow the evacuation of occupants and to provide a protected space from which to fight fires where an interior fire attack was necessary.

Evacuation models for building design include engineering hand calculations and computational tools which can be used to evaluate the level of safety provided by buildings during evacuation. Building designs and occupant procedures are based on the results...