Blast loads are defined by their “time history,” which is the trace of over-pressure throughout the load duration. An idealized blast time history is shown in the figure below (after UFC 3-340-01): The pressure (relative to ambient) is on the vertical axis and time is on the horizontal axis. The blast duration is generally taken […]
Articles
Six Steps to Specifying Blast Products
The world of blast protection has been rapidly expanding and there are now numerous products and approaches to provide protection from explosive attack. Where there used to be two solutions, there may now be ten. It is critical that security and design professionals understand the strengths and limitations of the various mitigation measures, and how […]
Blast Basics
An explosion is a rapid release of energy in the form of light, heat, sound, and a shock wave. The shock wave travels outward, in all directions, from the source of the explosion and is the primary source of building damage considered in blast resistant design. The duration of the shock wave is very short, […]
The Wonders of Rebar
Reinforced concrete is really a wonderful thing (the same goes for reinforced concrete masonry unit (CMU) block walls). We take two completely different types of materials (concrete and steel) and combine them to take advantage of the best of both materials. Concrete (and CMU) elements are strong in compression – like when gravity presses down […]
What Makes An Extraordinary Load Different?
As part of our day-to-day consulting practice, we deal with what can be termed as Extraordinary Loads. I was recently in a design meeting and when I mentioned what I consider to be a fairly low blast load, the structural engineer’s eyes widened. She said that this load would change the entire design, and she […]
Three Critical Elements to Include in RFP and Tender Documents ForBlast Resistant Design
Those of us who have been in the business of designing and building blast resistant buildings for a long time have seen RFP and Tender documents evolve from a single line statement (e.g. “Meet ISC Security Criteria”) to long lists of referenced documents and required approaches. The problem is, that if not carefully and meticulously […]