Designing Catch Benches and Interramp Slopes

Bench Heights. Currently, most large mining operations drill and blast on 12-to 15-m intervals (40 to SO ft), with 15-m intervals being the most common. The mining equipment used to drill and …

(PDF) Selection of blasthole diameter for a given bench height …

The combination of blasthole diameter and bench height was divided into three categories, each with its specific characteristics. ... Keeping the lid on ¯yrock in open-pit blasting. Eng. Mining ...

Influences of bench height of an open-pit coal mine on

Heidaigou open-pit coal mine was chosen as an example to explore the influences of bench height on cast blasting in open-pit coal mines. Theoretical analyses and site tests were carried out ...

RESEARCH ARTICLES Impact of blast design parameters …

to numerous factors, i.e. small area under mining lease, lower bench height, vicinity to residential and other struc-tures, higher degree of segregation of oversized boulders required after blasting, and heterogeneous geology, to name a few. The present study attempts to establish how blast design in Indian building stone quarries influences

Design of a surface blast

efficient blast in a surface mine without causing any recognizable hazards to the surroundings. 26.2 BLASTHOLES IN A MINE BENCH A blasthole drill stands on a mine bench top and drills blastholes in it. Blastholes drilled in the rock mass appear as shown in Figure 26.1.

Evaluation and optimization of blasting approaches to reducing oversize

The bench height is 10.5 m. The blasting fragmentation effects under different conditions are compared quantitatively. It should be noted that the specific charge for each case was kept the same. ... A system-wide approach to minimize the operational cost of bench production in open-cast mining operations. Int J Coal Sci Technol, 6 (1) (2019 ...

SUBDRILL THE UNDERUTILISED BLASTING PARAMETER

percentage of the bench height. • If the upper and lower patterns are different the technique cannot be used. 17. ... • Hustrulid, W. (1999). Blasting Principles for Open Pit Mining, Volume 1 - General Design Concepts. Boca Raton: Taylor and Francis Group. • Hustrulid, W. (1999). Blasting Principles for Open Pit Mining, Volume 2 ...

7 Rules of Thumb for Open Bit Blast Pattern

Below is 7 rules of thumb for open bit blast pattern. 1. Burden. 25 to 35 hole diameters; 2. Spacing . size greater than 140 mm (5½") 1.2 to 1.5 burden; Hole size smaller than 140 mm (5½") 1.5 to 1.8 burden; 3. Stemming . 0.7 to 1.3 burden. 4. Bench Height . 40 to 50 hole diameters; 5. Sub-drill . 8 hole diameters; 10 to 12 hole diameters ...

Selection of practical bench height in open pit mining …

Dilution versus bench height (Bozorgebrahimi et al., 2005). Figure 3. Large block of the simple sequencing method. In open pit mining, factors that can affect the degree of dilution can be regarded as deposit-related or mine-related. The bench height is a mine-related parameter that can be studied using a simple geometrical model of

Relation between blasthole diameter (d ) and bench height …

A method is proposed for bench blasting in open pit mines that can automatically determine the blastholes positions, calculate the explosive charge mass, and identifies the initiation sequence in ...

Optimal Blast Design Considering the Effects of …

Designed drill and blast parameters at New Cement Quarry (NCQ) Designed Parameters Bench height (m) Burden(m) Stemming height (m) Spacing between holes (m) Diameter of mine hole(mm) length of load (mm) Charge density of explosive (kg/m3) Hole length (m) Subdrilling hole (m) Total explosive quantity(kg) Symbol value BH B U S HD CL SDE HL SH TEQ ...

High-Level Blast Design Basics

Blast Design Parameters When designing a blast, several parameters are considered, including bench height, hole diameter, rock type, and explosive type. The fundamental principles of blasting are closely tied to hole …

Optimization Of Blasting Design Parameters On Open …

D=blast hole diameter (mm), W=standard deviation of the drilling accuracy (m), L=total charge length (m), H=Bench height (m).Cunningham (1987) notes that the uniformity coefficient n usually varies between 0.8 and 1.5 1.3 Bench Blasting Parameters Bench blasting in open pit operations are classified according to their purpose.

A Review of Contemporary Blast Design Data and Rules of …

Rules of thumb are ubiquitous in blasting. Typically presented as ratios, they assist with the initial assumptions of blast design and provide guidance for best practice. Examples include the blast hole diameter as a function of bench height, and stemming length as a function of hole diameter. The most common rules of thumb were developed in mid-20th century and it …

(PDF) DETERMINATION OF BENCH BLAST DESIGN …

Bench height, hole diameter, spacing, burden, hole length, bottom charge, column charge, stemming, specific hole length and specific charge are the design parameters in bench production blasting.

Blast design in opencast mining | PPT

Blast design in opencast mining - Download as a PDF or view online for free. ... In practice, burden = ½ to 1/3 of bench height. Spacing- distance between two consecutive holes in a row parallel to face. It should be adequate. In practice, spacing = 1.0 to 1.5 of burden. 9.

7.3.1: Bench Blasting | MNG 230: Introduction to Mining …

For benching, hole diameters typically range from a low of 3" to a high of 15". If we're benching in an underground mine, we'll have hole diameters near the low end of that range, and for surface …

Machine Learning Techniques for Predicting the …

graphical representation of the blast bench in its 2D dimensions (East-North). Figure 1. Blasting bench in an open pit mine The statistical analysis of the data indicated that the mean height of the drilled holes was 8.37 meters, with a variation of 0.13 and a standard deviation of 0.35. Additionally, there are

(PDF) Surface Mine Design

surface mining than for underground mining. In surface mining, blasting patterns have . ... Bench height: v ertical distance between upper and lower surfaces of a bench. It is .