Burden Suggested in Langefors' Formula Calculator

Langefors' Formula:

\[ BL = \frac{db}{33} \times \sqrt{\frac{Dp \times s}{c \times Df \times EV}} \]

Diameter of Drill Bit:

Degree of Packing:

kg/dm³

Weight Strength of Explosive:

Rock Constant:

Degree of Fraction:

Ratio of Spacing to Burden:

Burden Suggested (m):

1. What is Burden in Langefors' Formula?

Definition: Burden is the ratio of explosive weight to rock mass, determining efficient rock fragmentation in blasting operations.

Purpose: It helps mining and construction professionals determine the optimal burden for effective rock blasting.

2. How Does the Calculator Work?

The calculator uses Langefors' Formula:

\[ BL = \frac{db}{33} \times \sqrt{\frac{Dp \times s}{c \times Df \times EV}} \]

Where:

\( BL \) — Burden suggested (meters)
\( db \) — Diameter of drill bit (meters)
\( Dp \) — Degree of packing (kg/dm³)
\( s \) — Weight strength of explosive
\( c \) — Rock constant
\( Df \) — Degree of fraction
\( EV \) — Ratio of spacing to burden

Explanation: The formula calculates the optimal burden distance for effective rock fragmentation in blasting operations.

3. Importance of Burden Calculation

Details: Proper burden calculation ensures efficient rock fragmentation, safety in blasting operations, and cost-effective explosive use.

4. Using the Calculator

Tips: Enter all required parameters. The calculator provides default values based on typical scenarios. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical drill bit diameter for blasting?
A: Common diameters range from 75mm to 300mm (0.075m to 0.3m), depending on the scale of operations.

Q2: How is degree of packing determined?
A: It's calculated as the explosive weight per unit volume of the borehole, typically 3-3.5 kg/dm³ for ANFO.

Q3: What affects the rock constant?
A: Rock type, hardness, and geological conditions primarily determine the rock constant value.

Q4: Why is ratio of spacing to burden important?
A: This ratio affects fragmentation pattern and blast efficiency, typically ranging from 1 to 1.5.

Q5: How accurate is this calculation?
A: The calculation provides theoretical values; field conditions may require adjustments (±5% or more).