Bulk strength

In designing a gelatine explosive, the same questions must first be answered as in the case of all other explosives, namely, the bulk strength required and the degree of resistance to water. Again the practical requirement is to provide these properties with the minimum proportion of nitroglycerine. 

Bulk strength. The strength per unit volume of an explosive, usually expressed as a percentage of the strength per unit volume of blasting gelatine. 

Additional drawbacks to the use of polyimide insulators for the fabrication of multilevel structures include self- or auto-adhesion. It has been demonstrated that the interfacial strength of polyimide layers sequentially cast and cured depends on the interdiffusion between layers, which in turn depends on the cure time and temperature for both the first layer (Tj) and the combined first and second layers (T2) [3]. In this work, it was shown that unusually high diffusion distances ( 200 nm) were required to achieve bulk strength [3]. For T2 > Tj, the adhesion decreased with increasing T. However, for T2 < Tj and Tj 400 °C, the adhesion between the layers was poor irrespective of T2. Consequently, it is of interest to combine the desirable characteristics of polyimide with other materials in such a way as to produce a low stress, low dielectric constant, self-adhering material with the desirable processabiHty and mechanical properties of polyimide. 

Used in mining metallic ores, gypsum, limestone, in quarrying hard rock, and in construction work (Refs 1 2). Compositions are not given, but their bulk strengths, densities and detonation velocities are Listed in Ref 3 Refs 1) Cook (1958), 12 2) CondChem-... 

On the other hand in slabbing or rib shots, best results are usually obtd when the expl charge is well distributed thru the bore-hole. In the case of slabbing, a dense, high bulk strength explosive is required, while in the rib shots a low bulk strength explosive is advised... 

CA 61, 4143 (1964) (A high-bulk strength slurry-type blasting compn, such as contg AN 26.5, water 11.0, TNT 27.0, NaN03 15.0, ferrophosphorus 20.0 guar gum 0.5%)... 

To obtain high bulk strength it is, therefore, necessary to increase the d to the max possible. 

Same as Cartridge Strength or -> Bulk Strength. Also -> Weight Strength and -> Strength. 

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