Detonation characteristics of ammonite 6ZhV

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If the pressure at the Jouguet point has been determined and the shock adiabatic curve of the detonation products of a given explosive charge is known, one may calculate the pressure and mass velocities at the interface with rock, the shock adiabatic curves of which are known. Determination of the detonation parameters of a charge of given density gives only one point on the shock adiabatic curve of the explosion products Uouguet point). To consTxuct the shock adiabatic curve of the detonation products, we must know the equation of their state.However, as shown by Kuznetsov et al. [1], for these purposes the power-law relation between pressure and density, of the form p = Ap n (assuming that A and n ate constant, or taking account of the n vs 0 curve), is sufficiently accurate. To obtain the dependence of the polytropic exponent on the density of the products in powerful explosives, we may use the dependence of the detonation parameters on the initial density, assuming that the composition of the products does not vary greatly [2].It was initially felt that such a procedure could be used in the case in question. However, the results of investigations in [3] revealed that the pressure and density of the explosion products do not increase markedly with increasing initial density of the explosives, whereas the polytropic exponent does show a marked increase. For comparison, Fig. 1 shows the n vs 0 curve constructed from experimental data on hexogen, based on the D vs P0 and u vs p 0 curves. This figure also gives the points for ideal detonation conditions of ammonite 6ZhV of different densities. The composition of the detonation products of ammonite 6ZhV may differ markedly from that of the detonation products of hexogen, as may be seen from the polytropic exponents at the same pressures. However, this difference is not very great for ammonite 6ZhV with density 00 = 1.0 g/cmS; for 00 = 1.45 and 1.7 g/cm ~ the analogous points are located at a considerable distance from the n vs p curve of hexogen. This difference between the polytropic exponents for ammonite 6ZhV of different initial densities is apparently due to the change in the composition of the products with the density. The change in the polytropic exponent affects the shape of the shock adiabatic curves. This may be seen from Fig. 2, which gives the shock adiabatic curves of the explosion pto~cts of ammonite 6ZhV charges with • 0 = 1.0 g/era s and d = 80 ram, with the following parameters at the Jouguet point: p, = 75 9 10 ~ kg/em z and u, = 1.62 km/see (curves I and 2, starting from point A toward u > 1.62 km/sec). Curve 1 was constructed on the assumption that n = const = 1.8, in accordance with data for charges with O0 = 1.0 g/cm3~ curve 2 was constructed with an allowance for the n vs p curve from experimental data of D(p0) and u, (p 0). Mirror reflections of the corresponding adiabatic curves (see Fig. 2, curves 1' and 2' ) were constructed on the u < 1.62 krn/sec side. It will be seen from the position of the curves that an increase in the polytropic e...

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confidence: 70%

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confidence: 99%

Detonation of commercial explosives parameters of the shock waves produced at the explosives/rock boundary by the detonation of ammonite 6ZhV charges

Dremin¹,

Shvedov²,

Krivchenko³

et al. 1971

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“…The higher the energy capacity in the loading of the medium, the greater the value of c~. For example, for argillaceous silt, limestone,and marble, which have different energy capacitites, the ratio of the c~ values satisfies the inequality C~as > ali m > ama r (2) and their values are 0.1214, 0.0766, and 0.0442, respectively.…”

Section: E~ojmentioning

confidence: 95%

“…The experimental procedure and measurement methods for the wave parameters are discussed in [1][2][3].…”

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confidence: 99%

Assessment of the energy capacities of rocks in an explosion

Baranov¹,

Klapovskii²

1969

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The energy capacities of rocks may be assessed by taking account of the relative integral energy losses of the wave S as a function of the distance and their physicomechanical properties.In the physical sense the absolute integral losses S o express the difference in the energy levels corresponding to a quasielastic and elastico-plastic state of the medium under conditions of a dynamic explosive load at a certain relative distance ~ =R/r0, where r0 is the radius of the charge and R is the absolute distance to the investigated point.To determine the absolute integral losses S o in the purest form, uncomplicated by geometrical scattering of the wave energy in the space, it is desirable to effect explosive loading of the medium by charges which form a flat front. In each particular case the energy loss of the wave is calculated from the initial energy level El ~ determined for the given medium by the initial calculated and experimental values of the wave parametersthe pressure P, the velocity of the particles behind the front of the shock wave t at the charge-medium interface (with ~i = I. 0).The difference between the initial energy lev~. k of the wave and its current value E~ i) at a distance r-irepresents the actual absolute integral losses S O = E2 (~ E~ 11, and the relationship S -----So I g~2 ~ = ~[e(~ --e(0~,/ E(~ characterizes the relative integral losses of the wave energy.The initial and current values of the energy level of the wave E~ ~ and E~ i) were assessed for different relative distances ~ from the specific surface energy of the wave in the form: E(2 ~ '} = P2o, , tfpoDo, i , where the index 0 corresponds to the wave parameters (Tables 1 and 2) at the interface (r~ = 1.0), and the index i to the current values of the parameters in the range ~ from 1 to 5 r0.The pressure in the shock wave P0,i was calculated from the simultaneously measured values of the wave parameters Do, i and U0, i as P0, l = Po Do. l Uo, i .The experimental procedure and measurement methods for the wave parameters are discussed in [1][2][3].Using this procedure, we made an experimental assessment of the energy capacities of argillaceous silt, limestone, and marble in the vicinity of the effect of an explosion (1-5 r0), where the work (stress x strain) was maximal.Analysis of the exEerimental data* (see Table 1, Fig. 1) reveals that at a constant charge weight of the same explosive the value of Ez (i) is maximal for argillaceous silt, that of limestone being smaller, and that of marble minimal. High energy values are accompanied by maximal velocities of the particles behind the front, maximal residence times of the positive phase of the front, and maximal deformation (Fig. 2). The integral wave energy losses due to the effective fracturing work and irreversible processes increase more markedly at high deformations. This is confirmed by our experimental results (see Table 2, Fig. 3). It will be seen from the curve of S vs log7 that in the case of explosion loading the maximal relative integral energy losses S and the intensity of ...

Detonation of commercial explosives detonation characteristics of zernogranulit 80/20 and granulit as 8

Dremin¹,

Shvedov²,

Baranov³

et al. 1972

In this article we continue the series of investigations begun in [1,2]. All the experiments were performed on cylindrical charges of diameter 80-300 mrr~ The chargelength was usually three or four times the diameter; with a fairly powerful initiator (100-200 g of ammonite No. 6 or TNT). this enabled us to determine the detonation parameters under steady conditions. In certain cases (at virtually critical charge diameters) we used charges of various lengths in order to determine the steadiness of the explosion processes and to refine the values of the crRieal diameters.The charges were prepared by sprinkling the usual amount of explosives into thin cardboard sheaths. The 9 charging density was 1.0 g/em s. As the work progressed, it was necessary to use different batches of explosives.The experimental results exhibited marked scatter at virtually critical charge diameters. In this connection, we performed special experiments on the propagation of explosion processes in relation to the batch of explosive and its moisture content, which enabled us to assess the possible effect of random factors on the detonation parameters (caldng, wetting, etc.) which may come into play during practical use of explosives.