Changes in the relative costs of blasting in hard rocks due to an increase in the blast-hole charge diameter

Objective of the paper is to substantiate rational ore-stoping technique while using small wells in the context of thin-vein steeply inclined deposit mining. The technique is based upon the repeated field studies and simulation of ore drawing processes for shrinkage ore stoping in terms of the oriented drilling of periphery holes. A design of a blast-hole charge with low-density porous intermediate layer has been proposed as a result as well as a mechanism of shock-wave propagation within rock mass in the process of thin steeply inclined vein stoping. Scientific novelty is represented by means of analytical results of scientific sources, and dependences of ore losses on the vein wall hypsometry resulting from shrinkage stoping in the context of the technique being proposed. Practical relevance is to substantiate rational parameters of the ore-stoping technique being proposed. The technique involves designs of blast-hole charges with low-density porous intermediate layer in stemming. Moreover, the technique proposes to place the intermediate low-density stemming layer right after a blast hole was charged with explosives and live primers were inserted.

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Numerical simulation of the stress-strain state of a coal seam caused by an explosion of a blast-hole charge with an annular gap

EPJ Web of Conferences ◽

10.1051/epjconf/201922101053 ◽

2019 ◽

Vol 221 ◽

pp. 01053 ◽

Cited By ~ 2

Author(s):

Iwan Shipovskii ◽

Vladimir Odintsev

Keyword(s):

Numerical Simulation ◽

Computer Simulation ◽

Numerical Methods ◽

Strain State ◽

Blast Hole ◽

Dynamic Problems ◽

Deformable Solid ◽

Annular Gap ◽

Hole Charge ◽

Induced Defects

The computer simulation of the propagation of a blast wave generated by various explosives is carried out. The simulation used numerical methods to solve dynamic problems in the mechanics of a deformable solid, which allow one to investigate the development of waves during the explosion of charges of various shapes at different speeds of detonation of explosives and various conditions of placement of charges in the hole. The novelty of the research is related to analysis of conditions for the formation of a tensile pulse, which determines the opening of natural and induced defects in a zone remote from the explosion (from 20 to 100 radii of charge), which is known as the zone of explosive pre-fracture.

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Action of the explosion of a blast hole charge in the design of a direct cut with a compensation hole

Soviet Mining Science ◽

10.1007/bf02528513 ◽

1982 ◽

Vol 18 (2) ◽

pp. 119-122

Author(s):

É. P. Taran ◽

V. Ya. Shapiro

Keyword(s):

Blast Hole ◽

Hole Charge

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MODELLING THE DEVELOPMENT OF AXIALLY SYMMETRIC CRACKS IN THE EXPLOSION OF A BLAST-HOLE CHARGE

Interexpo GEO-Siberia ◽

10.33764/2618-981x-2019-2-5-112-119 ◽

2019 ◽

Vol 2 (5) ◽

pp. 112-119

Author(s):

Evgeny Sher

Keyword(s):

Free Surface ◽

Blast Hole ◽

Brittle Rock ◽

Axially Symmetric ◽

Tensile Stresses ◽

Tangential Stresses ◽

Hole Charge ◽

Radial Cracks ◽

Shape And Size

During explosion of buried blast-hole charges at brittle rock solid, main destruction of rock occurs by means of development of radial cracks specified by significant tensile tangential stresses near charge and along its surface. While explosion happens, near end faces of buried charges along its axis significant tensile stresses occur. Presence of such stresses can cause occurring and development of axially symmetric cracks. In the work calculating scheme of axially symmetric cracks development near end face of charge near free surface is developed. Examples of calculations of the shape and size of such cracksare carried out.

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Design method of blasthole charge structure based on lithology distribution

Scientific Reports ◽

10.1038/s41598-021-03758-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

YingXian Chen ◽

Jian Chen ◽

PengFei Wang ◽

Meng Zhou ◽

HongXia Yang ◽

...

Keyword(s):

Design Method ◽

Blast Hole ◽

Structure Design ◽

Open Pit ◽

Distribution Data ◽

Geological Exploration ◽

Charge Structure ◽

Drilling Rig ◽

Hard Rocks ◽

Rock Group

AbstractThe density of geological exploration boreholes is one of the main bases for blasthole charge structure design. Due to the low density of geological exploration boreholes, it is impossible to obtain the blast hole rock formations' distribution accurately. With the development and application of intelligent drilling rigs, the lithology distribution data of the blasthole can be accurately obtained, and a blasthole charge structure design method based on the lithology distribution is proposed. The blasthole lithology data collected by the intelligent drilling rig is divided into 7 categories according to the rock hardness, and the adjacent strata with similar lithology are combined and divided into two groups of soft rocks and hard rocks. According to the rock stratum grouping data of the blasthole and the unit explosive consumption of each type of lithology, the explosive amount and charge length required for the soft rock group and the hard rock group can be calculated, respectively. Finally, the blasthole charge structure is designed according to the thickness and charge position of the hard rocks. With the C++ programming language, this method is realized and applied in the Shengli Open-pit Coal Mine of Inner Mongolia Autonomous Region of China. The application results show that, compared with the traditional hole charging structure design method, this method can realize accurate segmented charging of the hole, improve the blasting effect and the degree of rock fragmentation, and reduce the blasting cost.

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Formation of breakage zone and microcracks with different striker positions in the blast hole charge

Soviet Mining Science ◽

10.1007/bf02497240 ◽

1988 ◽

Vol 24 (3) ◽

pp. 245-247

Author(s):

P. A. Kochetkov

Keyword(s):

Blast Hole ◽

Hole Charge

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Calculation of blast hole charge amount based on three-dimensional solid model of blasting rock mass

Scientific Reports ◽

10.1038/s41598-021-04615-8 ◽

2022 ◽

Vol 12 (1) ◽

Author(s):

YingXian Chen ◽

PengFei Wang ◽

Jian Chen ◽

Meng Zhou ◽

HongXia Yang ◽

...

Keyword(s):

Rock Mass ◽

Blast Hole ◽

Three Dimensional ◽

Open Pit ◽

Solid Model ◽

Mass Model ◽

Hole Charge ◽

Bench Blasting ◽

Drilling Rigs ◽

3D Solid

AbstractThe development and use of intelligent drilling rigs make it available to obtain accurate lithology data of blast drilling. In order to make full use of drilling data to improve blasting efficiency, the following research was carried out. First, a database is established to manage and store the blast hole data recognized by the intelligent drill. Secondly, the blast hole lithology data is taken as a sample, and the inverse distance square method is used to interpolate the blasting range's solid elements to generate a three-dimensional solid model of the blasting rock mass. Afterward, the blasting range polygon and stope triangle grid are used successively in the solid model to obtain the cut 3D solid model of the blasting rock mass; finally, the blast hole charge is calculated based on the cut 3D solid model of the blasting rock. The C++ programming language is used to realize all the blast hole charge amount processes based on the three-dimensional solid model of the blasting rock mass. With the application example of No. 918 bench blasting of Shengli Open-pit Coal Mine in Xilinhot, Inner Mongolia, the blast hole charge amount in the blasting area is calculated and compared with the results of single hole rock property calculation, the results show that the blast hole charge calculated by three-dimensional rock mass model can be effectively reduced.

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