CALCULATIONS BlastCalc and VibeSD
Created by Brent Buffham © 2021
Currently only available in Metric Units


Blasting Calculator

Vibration Calculator

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Calculations used in the Applications.
These are written in a Microsoft Excel Format for you to easily consume into your Excel sheets.
Replace the words with the appropriate cell Reference.


Vibration Scaled Distance - Formula from the AS2187.2 Appendix J.
Variables =
     VIBRATION (millimeters/second),
     KCONSTANT(1-10000),
     DISTANCE (meters),
     WEIGHT (kilograms),
     AVALUE (> -1.0; Generally -1.6),
     BVALUE (0.5 [square root]
Calculations =
     • VIBRATION = KCONSTANT * ( DISTANCE / ( POWER( WEIGHT, BVALUE ) ) )^AVALUE
     • KCONSTANT = VIBRATION / ( DISTANCE / POWER( WEIGHT, BVALUE) )^AVALUE
     • DISTANCE = POWER( ( VIBRATION / KCONSTANT ) , 1 / AVALUE )* POWER( WEIGHT, BVALUE )
     • WEIGHT = POWER( DISTANCE / POWER( ( VIBRATION / KCONSTANT) , 1 / AVALUE ),(1/BVALUE ))
     • AVALUE = LOG( VIBRATION / KCONSTANT) / LOG( DISTANCE / POWER( WEIGHT, BVALUE ))
     • BVALUE = LOG( DISTANCE * (POWER( ( KCONSTANT / VIBRATION ) , ( 1 / AVALUE )))) / LOG( WEIGHT )

Blasting Calculations - Various Sources.
     • HOLE INFLUENCE AREA = BURDEN * SPACING
     • HOLE INFLUENCE VOLUME = HOLE INFLUENCE AREA * BENCH HEIGHT
     • HOLE INFLUENCE TONNES = HOLE INFLUENCE AREA * ROCK DENSITY
     • PATTERN AREA = HOLE INFLUENCE AREA * NUMBER OF HOLES
     • UNCHARGED VOLUME = PATTERN AREA * (STEMMING LENGTH + INERT LENGTH)
     • UNCHARGED TONNES = UNCHARGED VOLUME * ROCK DENSITY
     • SIN ANGLE = SIN((90-HOLE ANGLE) * (PI() /180))
     • VERTICAL LENGTH = BENCH HEIGHT + SUBDRILL LENGTH
     • HOLE LENGTH = VERTICAL LENGTH / SIN ANGLE
     • HOLE RADIUS = (DIAMETER / 2) * 1000
     • VOLUME PER METER = (PI() * POWER(HOLE RADIUS, 2)) / 1000
     • VOLUME PER HOLE = VOLUME PER METER * HOLE LENGTH
     • VOLUME PER STEMMING LENGTH = VOLUME PER METER * STEMMING LENGTH
     • STEMMING MASS = VOLUME PER STEMMING LENGTH * STEMMING DENSITY
     • VOLUME PER INERT LENGTH = VOLUME PER METER * INERT LENGTH
     • CHARGE VOLUME = VOLUME PER HOLE - VOLUME PER INERT - volPerStemmingLength
     • CHARGE MASS = CHARGE VOLUME * PRODUCT DENSITY
     • TOTAL DRILL METERS = HOLE LENGTH * NUMBER OF HOLES
     • VOLUME PER INERT ZONE = VOLUME PER INERT LENGTH * NUMBER OF HOLES
     • CHARGE MASS PER METER = VOLUME PER METER * PRODUCT DENSITY
     • TOTAL CHARGE METERS = (HOLE LENGTH - INERT LENGTH - STEMMING LENGTH) * NUMBER OF HOLES
     • TOTAL EXPLOSIVE MASS = CHARGE MASS * NUMBER OF HOLES
     • TOTAL BLAST ROCK VOLUME = HOLE INFLUENCE VOLUME * NUMBER OF HOLES
     • TOTAL BLAST ROCK TONNES = HOLE INFLUENCE TONNES * NUMBER OF HOLES
     • POWDER FACTOR VOLUME = TOTAL EXPLOSIVE MASS / TOTAL BLAST ROCK VOLUME
     • POWDER FACTOR TONNES = TOTAL EXPLOSIVE MASS /TOTAL BLAST ROCK TONNES
     • VERTICAL ENERGY = (HOLE LENGTH - INERT LENGTH - STEMMING LENGTH) / HOLE LENGTH * 100
     • BURDEN STIFFNESS = BENCH HEIGHT / BURDEN
     • SPACING SPEED = SPACING DELAY TIME / SPACING
     • BURDEN SPEED = BURDEN DELAY TIME / BURDEN
     • STAGGERED HYPOTENUSE = POWER(POWER(BURDEN,2) + POWER((SPACING/2),2), 0.5 )
     • SQUARE HYPOTENUSE = POWER(POWER(BURDEN,2) + POWER(SPACING,2), 0.5 )
     • TIMING RELIEF STAGGERED = (SPACING DELAY TIME + BURDEN DELAY TIME) / STAGGERED HYPOTENUSE
     • TIMING RELIEF SQUARE = (SPACING DELAY TIME + BURDEN DELAY TIME) / SQUARE HYPOTENUSE
     • SDoBCONSTANT1 = 0.0005
     • SDoBCONSTANT2 = 0.00923
     • SDoBCONSTANT3 = 1/3
     • DIAMETER IN MM = DIAMETER * 1000
     • DIAMETER IN METERS = DIAMETER
     • LIMIT M VALUE GREATER THAN 100MM = 10
     • LIMIT M VALUE LESS THAN OR EQUAL TO 100MM = 8
     • M VALUE UNLIMITED = (HOLE LENGTH - STEMMING LENGTH) / DIAMETER IN MM
     • M VALUE = MIN(IF(DIAMETER IN MM < 100, 8, 10), (HOLE LENGTH - STEMMING LENGTH) / DIAMETER IN MM)
     • SCALED DEPTH OF BURIAL = (STEMMING LENGTH + (SDoBCONSTANT1 * M VALUE * DIAMETER IN MM) / (SDoBCONSTANT2 * DIAMETER IN MM * POWER((M VALUE * PRODUCT DENSITY),SDoBCONSTANT3))
     • DIAMETERS PER STEMMING LENGTH = STEMMING LENGTH / DIAMETER IN METERS;
     • DIAMETERS PER SUDRILL LENGTH = SUBDRILL LENGTH// DIAMETER IN METERS
     • DIAMETERS PER SPACING LENGTH = SPACING / DIAMETER IN METERS
     • DIAMETERS PER BURDEN LENGTH = BURDEN / DIAMETER IN METERS
     • DIAMETERS PER BENCH HEIGHT = BENCH HEIGHT// DIAMETER IN METERS
     • ANFO AMOUNT = TOTAL EXPLOSIVE MASS * ANFO PERCENTAGE
     • EMULSION OR MATRIX AMOUNT = TOTAL EXPLOSIVE MASS * EMULSION OR MATRIX PERCENTAGE
     • FUEL OIL AMOUNT = ANFO AMOUNT * FUEL OIL PERCENTAGE
     • AMMONIUM NITRATE AMOUNT = ANFO AMOUNT - FUEL OIL AMOUNT

Overpressure Scaled Distance - Formula from the AS2187.2 Appendix J.
Variables =
     DECIBELS (millimeters/second),
     KCONSTANT(1-100),
     DISTANCE (meters),
     WEIGHT (kilograms),
     AVALUE (> -1.0; Generally -1.45),
     BVALUE (0.3333 [cube root]
Calculations =
     • DECIBELS = =20 * LOG10((((KCONSTANT * POWER((DISTANCE / (POWER(WEIGHT, (AVALUE)))),BVALUE))) * 1000 / (2 * POWER(10, -5))))
     • KCONSTANT = =((((1000000000 * 0.00002) * POWER(10, DECIBELS / 20) / 1000000000) / 1000) / POWER(DISTANCE / POWER(WEIGHT, BVALUE), AVALUE))
     • DISTANCE = POWER((((1000000000 * 0.00002) * POWER(10, (DECIBELS / 20)) /1000000000 / KCONSTANT) / 1000), 1 / AVALUE) * POWER(WEIGHT, (BVALUE))
     • WEIGHT = POWER((DISTANCE / POWER(((((1000000000 * 0.00002) * POWER(10, (( DECIBELS) / 20)) / 1000000000) / 1000) / KCONSTANT), 1 / AVALUE)), (1 / BVALUE))
     • AVALUE = LOG10((((1000000000 * 0.00002) * POWER(10, ((DECIBELS) / 20)) / 1000000000) / 1000) / KCONSTANT) / (LOG10(DISTANCE / POWER(WEIGHT, (BVALUE))))
     • BVALUE = LOG10(DISTANCE * (POWER((KCONSTANT / (((1000000000 * 0.00002) * POWER(10, ( (DECIBELS) / 20)) / 1000000000) / 1000)), (1 / AVALUE)))) /LOG10(WEIGHT)


Ideal Decomposition of Nitromethane Chemistry Ideal and only relavant for a sense check.
     •3NH4NO3 + 2CH3NO2 -> 4N2 + 2CO2 + 9H2O


Thank you.

Brent Buffham © 2021.


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