Take Blasting Seriously, Engineer your blasts with Blaspa Simulators 

The Blaspa course will initiate the blasting professional on how to carry out blast studies with the Blaspa simulators to engineer blast solutions for different blasting tasks.  The course, given by Dr. Roger Favreau, will include a short theoretical section on the blasting mechanism that occur during the blast,  followed by two days of hands on experience using the Blaspa Simulators to solve practical blasting problems based on case histories.

From these courses, the blasting professional will gain:

• Practical in depth knowledge of blasting mechanisms that occur during a blast & how to use them to solve blasting problems.
• Hands on experience using the Blaspa simulators to engineer a blast.
• Evaluate the Blaspa simulators’ usefulness and potential at your operation.
• A Blaspa Course certification.

Course Agenda - Problems that can be address with the Blaspa Simulators presently on the Web:

1. How to eliminate toe and blocks - Shock wave stress contours:

  For a given bench blast procedure, the contour of any given shock wave stress level T is simulated and displayed inside the bench.  With T=To, the dynamic resistance of the given rock, it is possible to predict blocks in the collar zone, toe, possible back-break, etc.  With other values of T, it is possible to improve the fragmentation in a given zone of the bench.  This helps predict burden, collar, spacing, subgrade drilling, explosive type and distribution, etc. 

2. How to improve mucking -  Displacement profiles:

For a given bench blast procedure, the movement of the rock mass is simulated and displayed graphically at the face and inside the bench, at a time such as say 300 msec. after initiation; the numerical data can also be printed.  When doing simulation blast studies, this subroutine tends to be a most useful tool to evaluate and improve the mucking, as well as to address the aspect of horizontal dilution.  Experience shows that, once blocks, toe, etc are under control, producing loose muck is by far what a mine or quarry needs most for efficient operation.

3. How to evaluate the maximum burden - Semi-static stress fields at the face:  For a given bench blast procedure, this simulates the  intensity of the semi-static stress field by the time the latter reaches the face, for each column of explosive.  Knowledge of this, together with the shock wave stress contour, allows the maximum burden to be predicted.

4. How to control vibrations – Vibmas:

Evaluation of the ‘far’ vibrations caused by the rock mass movement during a blast.

5. How to control fly-rock:

  – Simulators* to predict the Maximum Flyrock from a Bench Blast:

• >Evaluation of the farthest reaching normal fly-rock from the front row for a given blasting procedure. 
• >Evaluation of the farthest reaching normal fly-rock from back rows for a given blasting procedure. >Evaluation of the farthest reaching normal fly-rock from a given blasting procedure, if a blasting mat is used on the top of the bench.

     -Simulator* to predict the Maximum Flyrock for a Blast to Open a Cut:

            >Evaluation of the farthest reaching normal fly-rock from a sinking cut, or frpm the top of the bench

             when the horizontal swell is inadequate to prevent upward movement of the rock mass.

* These simulators deal only with normal flyrock, excluding flyrock due to the direct push of the explosion gas.

6.  How to determine the optimum delay: 

For a given bench blast procedure, the velocity of the rock at the face is simulated and the optimum delay is calculated using the well proven Dupont Sequential Blasting (D. S. B.) criterion; it also allows the delay to be calculated according to any other choice of criterion.  The simulations calculate the following delays:

• >Evaluation of the Minimum Delay that must be used for each hole.
• >Evaluation of the optimum inter-row delay for best fragmentation, according to the Dupont-Sequential-Blasting criterion.
• >Evaluation of the Necessary Inter-row Delay to achieve adequate horizontal swell for the back rows, such that the rock of the back rows does not move up and cause excessive flyrock. 

7.  How to design pre-shear blasts – simulator Preshear:

Evaluation of the stress level created between holes by a given preshear blast procedure, thereby evaluating if the crack can propagate properly from hole to hole.

8.  Explosive rating in a specific rock:  In the 1950’s, Cook and others developed subroutines to calculate the thermo-chemistry of a given explosive formulation; these can supply the chemical energy which the explosive can release, as well as the total work energy it can perform under optimum conditions, both per gm.  During a blast, the work actually performed is much less than that under optimum conditions; in particular, this work in part turns to shock wave energy, and in part to movement and fragmentation, the amount of each depending on the type of rock being blasted.  Simulations with Blaspa take the rock into account and predict these partitions for a given rock.  Such information is of particular importance to an explosive supplier when he offers his products to a specific user, or when he develops a new explosive for a given market.  Thus the ability to simulate Brisance (shock wave energy) and Wef (effective energy) has been included in the subroutines on the web, for the sake of explosive suppliers.  It is also useful to a mine or quarry which is considering a change in the type of explosives it uses.