Strength of Building Elements When Subjected to Airblast

Abstract

A fair amount of information on the breakage of window glass by sonic booms and airblast is summarized in Siskind et al. 1980 , which was prepared by the Bureau of Mines. After a review of large quantities of data, an approximate threshold of window glass breakage was estimated in the range of 0.056 to 0.11 psi. Also, based on results from numerous investigators reviewed by the Bureau of Mines, the 50% probability of breakage for storefront windows 100 sq ft was estimated at 0.25 psi. The 50% probability of breakage for smaller windows designated as Colonial Pane 0.8 sq ft was estimated at 0.62 psi. Similar limiting values were also obtained from actual explosions of sticks of dynamite and reported in Siskind et al. 1980 . For example, when studying glass breakage from totally unconfined explosions, it was found that window glass damage could occur at cube-root-scaled distances as high as 260 ft / lb1/3. These data suggested a range of 0.032 to 0.290 psi, which values are mostly in line with those obtained from sonic boom data. It was also determined that breakage of window glass in structures should occur at lower overpressure levels than other damage such as cracking of plaster, for example.