Measurement of the spatial specific impulse distribution due to buried high explosive charge detonation

Abstract

Buried high explosive (HE) charges represent a high threat to military vehicles. The detonation of these charges can lead to significant momentum transfer onto vehicles and their occupants. A detailed understanding of the physical processes involved in the loading of vehicle structures is necessary for an optimization of effective countermeasures and protection systems. A quantitative description of the local momentum distribution on the vehicle underbody due to the detonation process is of special importance. In the following, a new test setup is presented that allows the experimental determination of the specific impulse distribution. It is based on a ring arrangement where the elements are nested into each other and the velocity of each ring is correlated with the local specific impulse at its position. The momentum transfer to a vehicle depends on a number of influencing factors such as: charge mass, embedding material (e.g. sand, gravel, clay), density, water content, saturation, depth of burial, ground clearance and vehicle shape. The presented technology is applied to quantify the influence of the embedding material (alluvial sand, quartz sand), the burial depth and the water content on the local specific impulse distribution. The obtained data can be used as initial condition for the numerical simulation of occupant safety assessment and as input for empirical modeling of momentum transfer on structures

The Effect of Soil Mineralogy and Particle Breakage on the Impulse Generated from Shallow Buried Charges

“…The Westine model [2] allows for a first-order approximation of the impulse from a buried charge to be calculated; however, the soil is categorised solely on its bulk density. More recent work has investigated additional parameters, including moisture content [4][5][6][7][8], void ratio and permeability [3,7,9,10], particle size distribution [3,7,11,12] and soil mineralogy (quartz [3,7,8,12], clays [3,4,7] and alluvial soils [8,12]).…”

Characterisation of buried blast loading

“…The magnitude of the total impulse imparted to a target has been shown to be influenced by geotechnical conditions such as moisture content/saturation [2][3][4][5][6][7][8][9][10][11][12], air voids and bulk density [6][7][8][9][10][11][12][13][14], and particle size distribution (PSD) [7][8][9][10][11][12], and by physical parameters such as depth of burial (DOB) [2,3,7,12,15,16] and stand-off distance (SOD) [3,6,15,[17][18][19]. However, while the effects of many geotechnical and physical parameters on total impulse have been quantified experimentally, to date there have been limited experimental studies on the localized development of load on a target [20][21][22][23], and none at larger scale.…”