Blasting Manual
This document was uploaded by user and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this DMCA report form. Report DMCA
Overview
Download & View Blasting Manual as PDF for free.
More details
- Words: 1,815
- Pages: 8
Loading documents preview...
THE BLASTER’S GUIDE
COMMON FORMULAS USED FOR BLAST DESIGN
BLAST DESIGN FORMULAS Absolute Bulk Strength (ABS) .................................................................................... Absolute Weight Strength (AWS) ................................................................................ Actual Scaled Distance ............................................................................................ Base-Charge Length ............................................................................................... Burden .................................................................................................................. Deck Stemming ......................................................................................................
8 8 8 8 9 9
-For Dry Holes -For Wet Holes
Face Height ........................................................................................................... 9 Hole-to-Hole Delay Time .......................................................................................... 9 Loading Density .................................................................................................... 10 Maximum Charge Weight per Delay .......................................................................... 10 Minimum Distance.................................................................................................. 10 Powder Factor ...................................................................................................... 10 -Volume of Rock Input -Weight of Rock Input
Pre-Splitting Formulas for Air-Decked Charges .......................................................... 11 -Spacing of Air-Decked Charges -Weight of Air-Decked Charges -Stemming Column Length
Pre-Splitting Formulas for De-Coupled Charges ......................................................... 11 -Linear Charge Weight -Spacing between Pre-Split Holes
Pressure Formula .................................................................................................. 11 Relative Weight Strength (RWS) ............................................................................... 12 Resistance Formulas ............................................................................................. 12 -For Paralle Circuits -For Series Circuits
Row-to-Row Delay Time ......................................................................................... 12 Stone Stemming Particle Size .................................................................................. 12 Spacing ............................................................................................................... 13 -Instant -Delayed
Sub-Drilling .......................................................................................................... “Supersonic” Face Velocity ..................................................................................... Top-Stemming Length ........................................................................................... Water Displacement .............................................................................................. Weight of Rock per Blast Hole ................................................................................. Vibration Level Prediction .......................................................................................
13 13 13 14 14 14
-Peak Particle Velocity Prediction -Site Specific Ground Transmission Constant
Volume of Rock per Blast Hole ................................................................................ 14
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
7
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS HOW TO READ FORMULAS
FORMULA NAME
FORMULA VARIABLES and [UNITS]
Variables used in formula and required units in [brackets]. If input variables are not in required units, then you must use the unit conversion tables.
Absolute Bulk Strength (ABS)
ABS E � AWSE � dE
Base-Charge Length Formula
Eb �
�� 0.3
VARIABLES and [UNITS]
E b = Length of base charge of high density explosives [ft] B = Average burden [ft] J = Sub-drilling depth [ft]
Acutual Scaled Distance Formula
Actual Scaled Distance
VARIABLES and [UNITS]
ABS E = Absolute bulk strength of the explosive [cal/cc] AWS E = Absolute weight strength of the explosive [cal/g] d E = Density of the explosive [g/cm 3 ]
SD �
RBS E � 7 . 462
AWS E = Absolute weight strength of the explosive [cal/g] RBS E = Relative bulk strength of the explosive [ANFO = 100] d E = Density of the explosive [g/cm 3 ] © 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
W
� D � W �� � � SD �
2
Minimum Distance
D � SD �
dE
VARIABLES and [UNITS]
D
Maximum Charge Weight per Delay
Absolute Weight Strength (AWS)
AWS E �
� 0.5 � � B � � J
W
VARIABLES and [UNITS]
SD = Scaled distance factor W = Charge weight per delay [ lb ] D = Distance [ft]
8
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Burden Formula Hole-to-Hole Delay Time Formula � � �d � B � De � ��2 � � e � � 1.5�� � � dr � �
D hth � � 0 � 5 � � S ms/ft
VARIABLES and [UNITS]
B = Burden [ft] de = Density of the explosives [g/cm 3 ] dr = Density of the rock [g/cm 3 ] De = Diameter of fully coupled explosive column [in]
VARIABLES and [UNITS]
Dhth = Delay time between holes in a row [ms] S = Spacing between holes in a row [ft]
Hole-to-Hole Delay Times to Improve Fragmentation
Deck Stemming Formula
For Dry Holes
Td � 0.5 � D
For Wet Holes
Td � 1.0 � D
VARIABLES and [UNITS]
Rock Type
ms/ft
Sands, Loams, Marls and Coals
1.8 - 2.1
Some Limestones, Rock Shale and some Shales
1.5 - 1.8
Compact Limestones and Marbles, some Granites and Basalts, Quartzite Rocks and some Gneisses and Gabbros
1.2 - 1.5
Diabase, Diabase Porphyrites, Compact Gneisses, and Mica Schists and Magnetites
0.9 - 1.2
Td = Minimum length of stone deck consisting of particles of size Ts [ft] D = Blast-hole diameter [in]
Face Height Formula
H�
5
10 � D
VARIABLES and [UNITS]
H = Face Height [ft]
Leading underground mining technology.
D = Blast-hole Diameter [in]
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
9
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Loading Density Formula
2
d l � 0.3404 � De � d e
Minimum Distance Formula
D � SD �
W
VARIABLES and [UNITS]
VARIABLES and [UNITS]
d l = Explosives loading density [lb /ft] De = Diameter of explosives column [in] de = Density of explosives [g/cm 3 ]
SD = Scaled distance factor W = Charge weight per delay [lb] D = Distance [ft]
Powder Factor Formula Volume of Rock
PF �
We V
VARIABLES and [UNITS]
Loading a blast on an iron ore range.
PF = Powder factor [lb/yd 3 ] We = Total weight of explosives used in blast [lb] V = Total volume of rock generated in blast [yd3 ]
Maximum Charge Weight per Delay
� D � � � SD �
Weight of Rock
PF �
2
W �� VARIABLES and [UNITS]
SD = Scaled distance factor W = Charge weight per delay [ lb] D = Distance [ft]
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
Wr We
VARIABLES and [UNITS]
PF = Powder factor [t/lb] Wr = Total weight of rock generated in blast [t] We = Total weight of explosives used in blast [lb]
10
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Pre-Splitting Formulas for Air-Decked Charges
Pre-Splitting Formulas for De-Coupled Charges Linear Charge Weight
Spacing of Air-Decked Charges
S
2
D Wl � 28
� �1 .5 � 2 .0 � � D VARIABLES and [UNITS]
VARIABLES and [UNITS]
S = Spacing between air-decked holes [ft] D = Diameter of blast-hole [in]
Wl = Linear charge weight for pre-splitting explosive [lb/ft] D = Diameter of blast-hole [in]
Spacing between Pre-Split Holes Weight of Air-Decked Charges
W
S�
� �0 .08 � 0 .12 � � S � Lh
D
2
2.8
VARIABLES and [UNITS] VARIABLES and [UNITS]
S = Spacing between pre-split holes [ft] D = Diameter of blast-hole [in]
W = Weight of air-deck charge [lb] S = Spacing between blast-holes [ft] Lh = Length of blast-hole [ft]
Pressure Formula Stemming Column Length
T � �1 .0 � 1 .2 � � D VARIABLES and [UNITS]
T = Stemming column length [ft] D = Diameter of blast-hole [in]
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
2
P � 0.000000233 � VOD � d E VARIABLES and [UNITS]
P = Pressure [kbar] VOD = Velocity of detonation of explosive [ft/sec] d E = Density of explosive [g/cm 3 ]
11
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Relative Weight Strength (RWS) Row-to-Row Delay Time Formula RWS E �
AWS E 91,000
Drtr � � 2 � 15 � � B ms/ft
VARIABLES and [UNITS]
RWS E = Relative weight strength of the explosive [ANFO = 100] AWS E = Absolute weight strength of the explosive [cal/g]
VARIABLES and [UNITS]
D rtr = Delay time between consecutive rows [ms] B = Maximum burden in front of a row of holes [ft]
Effects of Various Row-to-Row Delays
Resistance Formulas
For Parallel Circuits 1 1 1 1 1 � � � � ... � Rtotal R1 R2 R3 Rn
Effects
ms/ft
Violent excessive air-blast and back-break
2
High pile close to face, moderate air-blast and back-break
2-3
Average pile height, average air-blast and back-break
3-4
Scattered pile with minimum back-break
4-6
For Series Circuits Rtotal � R1 � R2 � R3 � ... � Rn
Stone Stemming Particle Size Formula
VARIABLES and [UNITS]
Rtotal = Total resistance of the electrical circuit [ �] R1 ... R n = Resistance of individual blasting caps or circuit branches [ �]
Ts �
D 12 � 20
VARIABLES and [UNITS]
T s = Clean crushed stone stemming particle size [in] D = Blast-hole diameter [in]
Bulk trucks preparing for another day on the job. © 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
12
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Sub-Drilling Formula Spacing Formulas J � � 0.2 � 0.5 � � B If: VARIABLES and [UNITS]
B = Burden [ft] J = Sub-drilling [ft]
H �4 B
If:
Instant
S � 2.0 � B
S�
Delayed
S � 1.4 � B
S�
H <4 B
H � (2 � B ) 3 H � (7 � B ) 8
VARIABLES and [UNITS]
H = Face height [ft] B = Burden [ft] S = Blast-hole spacing [ft]
Top Stemming Length Formula Industry’s leading Detonating Cord
T � � 0 .7 � 1 .3 � � B "Supersonic" Face Velocity Formula
D min �
S
VARIABLES and [UNITS]
B = Burden [ft] T = Top stemming length [ft]
1.127
VARIABLES and [UNITS]
D min = In order to avoid air-blast from "supersonic" lateral face velocity, the delay between holes must be more than Dmin [ms] S = Spacing between blast holes [ft]
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
13
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Water Displacement Formula
C
�
Lw
Lc
� Dc � �� D � h�
Vibration Level Predictation Formulas Peak Particle Velocity Prediction
2
1 � �� VARIABLES and [UNITS]
PPV � K � SD
- 1.6
VARIABLES and [UNITS]
C = Number of explosives cartridges required to rise above standing water L w = Length of the standing water column [ft] L c = Length of one explosives cartridge [ft] D c = Diameter of explosives cartridges [in] D h = Diameter of blast-hole [in]
PPV = Peak particle velocity [in/s] K = Ground transmission constant [K=160 if no other seismic data is available] SD = Scaled distance factor
Site Specific Ground Transmission Constant 1.6 K � PPV � SD
VARIABLES and [UNITS]
K = Ground transmission constant PPV = Peak particle velocity [in/s] SD = Scaled distance factor
HEET Truck on display at an open house in 2001
Weight of Rock per Blast Hole Formula
W � V � dr VARIABLES and [UNITS]
W = Weight of rock generated per blast-hole [t] V = Bank volume of rock generated per blast-hole [yd 3 ] d r = Bank density of rock [t/yd 3 ]
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
Volume of Rock per Blast Hole Formula
V�
B� S� H 27
VARIABLES and [UNITS]
V = Bank volume of rock per blast-hole [yd 3 ] B = Burden [ft] S = Spacing [ft] H = Face height [ft]
14
COMMON FORMULAS USED FOR BLAST DESIGN
BLAST DESIGN FORMULAS Absolute Bulk Strength (ABS) .................................................................................... Absolute Weight Strength (AWS) ................................................................................ Actual Scaled Distance ............................................................................................ Base-Charge Length ............................................................................................... Burden .................................................................................................................. Deck Stemming ......................................................................................................
8 8 8 8 9 9
-For Dry Holes -For Wet Holes
Face Height ........................................................................................................... 9 Hole-to-Hole Delay Time .......................................................................................... 9 Loading Density .................................................................................................... 10 Maximum Charge Weight per Delay .......................................................................... 10 Minimum Distance.................................................................................................. 10 Powder Factor ...................................................................................................... 10 -Volume of Rock Input -Weight of Rock Input
Pre-Splitting Formulas for Air-Decked Charges .......................................................... 11 -Spacing of Air-Decked Charges -Weight of Air-Decked Charges -Stemming Column Length
Pre-Splitting Formulas for De-Coupled Charges ......................................................... 11 -Linear Charge Weight -Spacing between Pre-Split Holes
Pressure Formula .................................................................................................. 11 Relative Weight Strength (RWS) ............................................................................... 12 Resistance Formulas ............................................................................................. 12 -For Paralle Circuits -For Series Circuits
Row-to-Row Delay Time ......................................................................................... 12 Stone Stemming Particle Size .................................................................................. 12 Spacing ............................................................................................................... 13 -Instant -Delayed
Sub-Drilling .......................................................................................................... “Supersonic” Face Velocity ..................................................................................... Top-Stemming Length ........................................................................................... Water Displacement .............................................................................................. Weight of Rock per Blast Hole ................................................................................. Vibration Level Prediction .......................................................................................
13 13 13 14 14 14
-Peak Particle Velocity Prediction -Site Specific Ground Transmission Constant
Volume of Rock per Blast Hole ................................................................................ 14
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
7
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS HOW TO READ FORMULAS
FORMULA NAME
FORMULA VARIABLES and [UNITS]
Variables used in formula and required units in [brackets]. If input variables are not in required units, then you must use the unit conversion tables.
Absolute Bulk Strength (ABS)
ABS E � AWSE � dE
Base-Charge Length Formula
Eb �
�� 0.3
VARIABLES and [UNITS]
E b = Length of base charge of high density explosives [ft] B = Average burden [ft] J = Sub-drilling depth [ft]
Acutual Scaled Distance Formula
Actual Scaled Distance
VARIABLES and [UNITS]
ABS E = Absolute bulk strength of the explosive [cal/cc] AWS E = Absolute weight strength of the explosive [cal/g] d E = Density of the explosive [g/cm 3 ]
SD �
RBS E � 7 . 462
AWS E = Absolute weight strength of the explosive [cal/g] RBS E = Relative bulk strength of the explosive [ANFO = 100] d E = Density of the explosive [g/cm 3 ] © 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
W
� D � W �� � � SD �
2
Minimum Distance
D � SD �
dE
VARIABLES and [UNITS]
D
Maximum Charge Weight per Delay
Absolute Weight Strength (AWS)
AWS E �
� 0.5 � � B � � J
W
VARIABLES and [UNITS]
SD = Scaled distance factor W = Charge weight per delay [ lb ] D = Distance [ft]
8
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Burden Formula Hole-to-Hole Delay Time Formula � � �d � B � De � ��2 � � e � � 1.5�� � � dr � �
D hth � � 0 � 5 � � S ms/ft
VARIABLES and [UNITS]
B = Burden [ft] de = Density of the explosives [g/cm 3 ] dr = Density of the rock [g/cm 3 ] De = Diameter of fully coupled explosive column [in]
VARIABLES and [UNITS]
Dhth = Delay time between holes in a row [ms] S = Spacing between holes in a row [ft]
Hole-to-Hole Delay Times to Improve Fragmentation
Deck Stemming Formula
For Dry Holes
Td � 0.5 � D
For Wet Holes
Td � 1.0 � D
VARIABLES and [UNITS]
Rock Type
ms/ft
Sands, Loams, Marls and Coals
1.8 - 2.1
Some Limestones, Rock Shale and some Shales
1.5 - 1.8
Compact Limestones and Marbles, some Granites and Basalts, Quartzite Rocks and some Gneisses and Gabbros
1.2 - 1.5
Diabase, Diabase Porphyrites, Compact Gneisses, and Mica Schists and Magnetites
0.9 - 1.2
Td = Minimum length of stone deck consisting of particles of size Ts [ft] D = Blast-hole diameter [in]
Face Height Formula
H�
5
10 � D
VARIABLES and [UNITS]
H = Face Height [ft]
Leading underground mining technology.
D = Blast-hole Diameter [in]
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
9
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Loading Density Formula
2
d l � 0.3404 � De � d e
Minimum Distance Formula
D � SD �
W
VARIABLES and [UNITS]
VARIABLES and [UNITS]
d l = Explosives loading density [lb /ft] De = Diameter of explosives column [in] de = Density of explosives [g/cm 3 ]
SD = Scaled distance factor W = Charge weight per delay [lb] D = Distance [ft]
Powder Factor Formula Volume of Rock
PF �
We V
VARIABLES and [UNITS]
Loading a blast on an iron ore range.
PF = Powder factor [lb/yd 3 ] We = Total weight of explosives used in blast [lb] V = Total volume of rock generated in blast [yd3 ]
Maximum Charge Weight per Delay
� D � � � SD �
Weight of Rock
PF �
2
W �� VARIABLES and [UNITS]
SD = Scaled distance factor W = Charge weight per delay [ lb] D = Distance [ft]
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
Wr We
VARIABLES and [UNITS]
PF = Powder factor [t/lb] Wr = Total weight of rock generated in blast [t] We = Total weight of explosives used in blast [lb]
10
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Pre-Splitting Formulas for Air-Decked Charges
Pre-Splitting Formulas for De-Coupled Charges Linear Charge Weight
Spacing of Air-Decked Charges
S
2
D Wl � 28
� �1 .5 � 2 .0 � � D VARIABLES and [UNITS]
VARIABLES and [UNITS]
S = Spacing between air-decked holes [ft] D = Diameter of blast-hole [in]
Wl = Linear charge weight for pre-splitting explosive [lb/ft] D = Diameter of blast-hole [in]
Spacing between Pre-Split Holes Weight of Air-Decked Charges
W
S�
� �0 .08 � 0 .12 � � S � Lh
D
2
2.8
VARIABLES and [UNITS] VARIABLES and [UNITS]
S = Spacing between pre-split holes [ft] D = Diameter of blast-hole [in]
W = Weight of air-deck charge [lb] S = Spacing between blast-holes [ft] Lh = Length of blast-hole [ft]
Pressure Formula Stemming Column Length
T � �1 .0 � 1 .2 � � D VARIABLES and [UNITS]
T = Stemming column length [ft] D = Diameter of blast-hole [in]
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
2
P � 0.000000233 � VOD � d E VARIABLES and [UNITS]
P = Pressure [kbar] VOD = Velocity of detonation of explosive [ft/sec] d E = Density of explosive [g/cm 3 ]
11
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Relative Weight Strength (RWS) Row-to-Row Delay Time Formula RWS E �
AWS E 91,000
Drtr � � 2 � 15 � � B ms/ft
VARIABLES and [UNITS]
RWS E = Relative weight strength of the explosive [ANFO = 100] AWS E = Absolute weight strength of the explosive [cal/g]
VARIABLES and [UNITS]
D rtr = Delay time between consecutive rows [ms] B = Maximum burden in front of a row of holes [ft]
Effects of Various Row-to-Row Delays
Resistance Formulas
For Parallel Circuits 1 1 1 1 1 � � � � ... � Rtotal R1 R2 R3 Rn
Effects
ms/ft
Violent excessive air-blast and back-break
2
High pile close to face, moderate air-blast and back-break
2-3
Average pile height, average air-blast and back-break
3-4
Scattered pile with minimum back-break
4-6
For Series Circuits Rtotal � R1 � R2 � R3 � ... � Rn
Stone Stemming Particle Size Formula
VARIABLES and [UNITS]
Rtotal = Total resistance of the electrical circuit [ �] R1 ... R n = Resistance of individual blasting caps or circuit branches [ �]
Ts �
D 12 � 20
VARIABLES and [UNITS]
T s = Clean crushed stone stemming particle size [in] D = Blast-hole diameter [in]
Bulk trucks preparing for another day on the job. © 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
12
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Sub-Drilling Formula Spacing Formulas J � � 0.2 � 0.5 � � B If: VARIABLES and [UNITS]
B = Burden [ft] J = Sub-drilling [ft]
H �4 B
If:
Instant
S � 2.0 � B
S�
Delayed
S � 1.4 � B
S�
H <4 B
H � (2 � B ) 3 H � (7 � B ) 8
VARIABLES and [UNITS]
H = Face height [ft] B = Burden [ft] S = Blast-hole spacing [ft]
Top Stemming Length Formula Industry’s leading Detonating Cord
T � � 0 .7 � 1 .3 � � B "Supersonic" Face Velocity Formula
D min �
S
VARIABLES and [UNITS]
B = Burden [ft] T = Top stemming length [ft]
1.127
VARIABLES and [UNITS]
D min = In order to avoid air-blast from "supersonic" lateral face velocity, the delay between holes must be more than Dmin [ms] S = Spacing between blast holes [ft]
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
13
THE BLASTER’S GUIDE
BLAST DESIGN FORMULAS
Water Displacement Formula
C
�
Lw
Lc
� Dc � �� D � h�
Vibration Level Predictation Formulas Peak Particle Velocity Prediction
2
1 � �� VARIABLES and [UNITS]
PPV � K � SD
- 1.6
VARIABLES and [UNITS]
C = Number of explosives cartridges required to rise above standing water L w = Length of the standing water column [ft] L c = Length of one explosives cartridge [ft] D c = Diameter of explosives cartridges [in] D h = Diameter of blast-hole [in]
PPV = Peak particle velocity [in/s] K = Ground transmission constant [K=160 if no other seismic data is available] SD = Scaled distance factor
Site Specific Ground Transmission Constant 1.6 K � PPV � SD
VARIABLES and [UNITS]
K = Ground transmission constant PPV = Peak particle velocity [in/s] SD = Scaled distance factor
HEET Truck on display at an open house in 2001
Weight of Rock per Blast Hole Formula
W � V � dr VARIABLES and [UNITS]
W = Weight of rock generated per blast-hole [t] V = Bank volume of rock generated per blast-hole [yd 3 ] d r = Bank density of rock [t/yd 3 ]
© 2 0 0 2 AU S T I N PO W DE R C O M P AN Y
Volume of Rock per Blast Hole Formula
V�
B� S� H 27
VARIABLES and [UNITS]
V = Bank volume of rock per blast-hole [yd 3 ] B = Burden [ft] S = Spacing [ft] H = Face height [ft]
14
Related Documents
Blasting Manual
January 2021 1
Controlled Blasting
January 2021 1
Sand Blasting
January 2021 0
Characterising The Blasting
February 2021 0
Protocolo Split Blasting
February 2021 0
Blasting Practices In Mines
January 2021 1More Documents from "partha das sharma"