Vibration/Airblast

Vibration/Airblast management

The vibration/airblast management module is used for tracking and visualizing historical data, and using it to build continually improving prediction models for each monitor location.

The main screen is accessible from the site page (where you see the project list)

To navigate to the module, select the "Vibration & Airblast" tab from the top of the sidebar (above the list of projects)

You will see outlines for all the projects that contain shot plans along with circle markers showing each monitor location.

You can change the coloring of the projects on the map to show the magnitude of vibration or airblast at any monitor location using the drop down menus in the sidebar.

Creating a new monitor location

Click the "Add Monitor Location" button in the sidebar to create a new monitor.

Then fill in the Monitor Location Name along with the GPS coordinates to finish setting it up.

Next you can set visual orange and red limits to highlight measurements that exceed those levels.

Users commonly set these to the statutory limits for that jurisdiction or to specific monitor limits arranged with stakeholders.

Adding data and creating a prediction model

You can then add historical vibration and airblast data for each blast and the software will automatically generate a prediction model for Vector Sum PPV using the standard Scaled Distance formula.

You need at least three blasts entered before it will generate a model.

The software will automatically calculate scaled distance where you have loading and timing information and will allow you to manually enter this number if you only have drilling information. If you do not have a shot plan (drilling design) in a specific project then that project will not appear in the list.

This model will be automatically used for future predictions during the shot design process.

The "Predicted PPV" line on the graph represents the model's best guess at what the Vector Sum PPV will be.

The "95% Predicted PPV" represents the line that the model is 95% sure that the Vector Sum PPV will fall beneath.

The non-owned structure checkbox determines where the results will be shown on the blast report but does not affect any of the calculations.

Clicking the "Time" toggle shows you a historical record of all blasts coloured based on the orange and red limits set.

Vibration/Airblast Prediction

Creating a prediction

The Vibration and Airblast Prediction module is accessed from within a project in the "Blast Prediction" folder in the sidebar.

The module pulls information from the shotplan runs it through the model built from historic site vibration data to automatically generate a prediction with no inputs required from the user.

It works out a scaled distance number using the distance between the monitor and the closest hole as well as the maximum instantaneous charge firing within an 8ms time window.

Values above the orange and red limits are coloured in the prediction table.

The "Predicted PPV" value represents the model's best guess at what the PPV will be.

The "95% Predicted PPV" represents the value that the model is 95% sure that the actual PPV will fall beneath.

If desired, you can manually edit the maximum instantaneous charge using the checkbox. You might do this to quickly test the impact of a design change without having to go to the design modules.

You can also manually edit the model parameters (K and N factors) using the checkbox. You might do this if you don't have sufficient historic data yet for a reliable model. In this case, the custom values will apply to all monitor locations for this prediction but will not impact other predictions.

Prediction reporting

Clicking on the "Download Report" button generates a printable report that shows all the detail from the prediction module.