TY  - JOUR
T1  - Measuring the Optimal Focal Distance to Make “Initial”
Cavity in the Mass of Solid Natural Resources
AU - Argimbaev, Kaerbek Rafkatovich AU - Alexandrovich, Isheysky Valentin 
JO  - Research Journal of Applied Sciences
VL  - 11
IS  - 5
SP  - 240
EP  - 244
PY  - 2016
DA  - 2001/08/19
SN  - 1815-932x
DO  - rjasci.2016.240.244
UR  - https://makhillpublications.co/view-article.php?doi=rjasci.2016.240.244
KW  - Blasting operations
KW  -blast hole
KW  -cumulative column charge
KW  -rock mass
KW  -cumulative jet
KW  -focal distance
KW  -initial cavity
AB  - This study describes the complex approach to study the formation process of the cumulative jet and the depth of its implementation into marble and granite in case of rock directional shattering by means of cumulative column charges. As a source of directional explosion we used a cumulative column charge in metal coating. In accordance with the values of measured depths after implementing the cumulative jet into rock plates we got numerical values of “initial” cavity scale depending on the focal distance for different charge types. We describe a model experiment aimed at the study of cumulative jet implementation mechanism and creation of stress concentrator (of the “initial” cavity). There is an X-ray picture here to show the process of implementing cumulative jet into a rock plate and there are results of lab experiments to study the depth of jet implementation at different focal distances. We show the scheme of interaction of separate cumulative jet fragments with the rock. It was revealed how the mass velocities in reflected shock wave for a jet rear side depend on the jet front side velocity for marble and granite. The connection of the implementation depth of the cumulative jet with the distance to the mass became clear.
ER  -