Abstract
Blast load calculations are a central aspect to most Facility Siting Studies (FSS) and Quantitative Risk Assessments (QRA) for chemical processing facilities. The calculated blast loads can have important impacts on new buildings at an existing facility that need to be properly understood for them to become design basis loads.
This paper describes an efficient and cost effective method of selecting a building design that minimizes blast risk to the extent practical;Firstly, by reviewing predicted blast loads and associated frequencies to select potential building types that can be used to achieve the required level of personnel protection, such as pre-engineered steel frames, masonry building with load-bearing walls, and precast concrete tilt-up construction.
Secondly, by developing structural models for each of the building types considered based on dynamic structural analyses of typical building components. The buildings’ blast load resistance can be graphically represented through pressure-impulse diagrams.
Thirdly, by investigating the sensitivity of a building’s blast capacity to changes for each building model by modifying structural properties such as roof components, exterior walls and other critical components of the building.
Fourthly, by determining a potential location for the building in the plant where a selected building construction type can be placed without exceeding a tolerable risk level.
Finally, by estimating the additional construction cost to locate the building at other locations where blast loads are more severe.
This paper assists in selecting cost-effective building design(s) to be considered in the planning and design stages by evaluating the material requirements of each building type to achieve acceptable performance. Sensitivity calculations can be performed to compare risk as a function of construction costs to allow a practical design to be selected.
