Quarry surveys

Periodic surveys of quarries for accurate and reliable monitoring.

 In the same way as for volumetric surveys, the point cloud is a particularly suitable form of data. It can be obtained in different ways depending on the specification :

• airborne lidar ;
• laser scanning with fixed stations ;
• terrestrial photogrammetry ;
• helicopter-borne photogrammetry ;
• UAV (drone) photogrammetry.

Regardless of the method used, the result will be a point cloud of high density (one point per 5 to 10 cm for this type of application).

Once the point cloud has been combined and georeferenced, the processing becomes identical, whatever the method of survey.

Suitable processes are :

• 3D mesh model (triangular irregular network or TIN) of the situation at time t ;
• comparison of the situation at time t with an earlier epoch ;
• extraction of profiles ;
• extraction of contours.