Influence of particle size distribution on the blast pressure profile from explosives buried in saturated soils

• Published in: Shock waves 2018-05, Vol.28 (3), p.613-626
• Main Authors: Rigby, S. E., Fay, S. D., Tyas, A., Clarke, S. D., Reay, J. J., Warren, J. A., Gant, M., Elgy, I.
• Format: Article
• Language: English
• Subjects: Acoustics; Blasting (explosive); Cohesion; Cohesionless soils; Condensed Matter Physics; Detonation; Engineering; Engineering Fluid Dynamics; Engineering Thermodynamics; Explosions; Explosives; Fluid- and Aerodynamics; Gravel; Heat and Mass Transfer; Original Article; Particle size; Particle size distribution; Pressure bars; Saturated soils; Soils; Split Hopkinson pressure bars; Stress concentration; Temporal distribution; Thermodynamics
• ISSN: 0938-1287; 1432-2153
• DOI: 10.1007/s00193-017-0727-7

The spatial and temporal distribution of pressure and impulse from explosives buried in saturated cohesive and cohesionless soils has been measured experimentally for the first time. Ten experiments have been conducted at quarter-scale, where localised pressure loading was measured using an array of 17 Hopkinson pressure bars. The blast pressure measurements are used in conjunction with high-speed video filmed at 140,000 fps to investigate in detail the physical processes occurring at the loaded face. Two coarse cohesionless soils and one fine cohesive soil were tested: a relatively uniform sand, a well-graded sandy gravel, and a fine-grained clay. The results show that there is a single fundamental loading mechanism when explosives are detonated in saturated soil, invariant of particle size and soil cohesion. It is also shown that variability in localised loading is intrinsically linked to the particle size distribution of the surrounding soil.