Blast Effects & Damage Assessment Flashcards
7 cards from real CES practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Blast Effects & Damage Assessment flashcards as text
Ground shock from a surface explosion is characterized by which wave type traveling through the earth?
Answer: Rayleigh and body waves (P and S waves)
Explosion-induced ground shock generates both body waves (compressional P-waves and shear S-waves) and surface waves (Rayleigh waves) in the soil or rock.
The standoff distance at which the Mach stem triple point forms determines the:
Answer: Height of burst required to maximize surface overpressure
Optimizing the height of burst (HOB) positions the Mach stem triple point at ground level, maximizing the overpressure delivered across the target area.
Tertiary blast injuries are caused by:
Answer: The victim being displaced and impacting a secondary surface
Tertiary blast injuries occur when the blast wind physically throws victims who then sustain blunt trauma from striking the ground, walls, or debris.
In assessing post-blast structural damage, a 'level 5' damage classification under UFC 3-340 generally means:
Answer: Collapse of primary structural members
UFC 3-340-02 Level 5 (Hazardous) damage corresponds to failure of primary load-bearing members and potential or actual collapse.
Which soil condition MOST amplifies ground shock transmitted to a nearby structure's foundation?
Answer: Saturated soft clay
Saturated soft clay has high impedance for compression wave transmission and low damping, amplifying ground motion transferred to structures.
The 'safe separation distance' for personnel exposed to an open-air detonation is primarily governed by:
Answer: Peak overpressure and fragment throw distance thresholds for injury
Safe separation distance is calculated so that both blast overpressure and primary/secondary fragmentation hazard zones are cleared for all personnel.
Which analytical model is most commonly used to predict far-field air blast overpressure from a hemispherical surface burst of TNT?
Answer: Hopkinson-Cranz (cube-root) scaling laws with Kingery-Bulmash curves
Hopkinson-Cranz scaling combined with Kingery-Bulmash empirical curves is the standard method for predicting air blast parameters from surface bursts.