Skip to main content
Conference Proceedings

Third International Symposium on Rock Fragmentation by Blasting, Brisbane, August 1990

Conference Proceedings

Third International Symposium on Rock Fragmentation by Blasting, Brisbane, August 1990

PDF Add to cart

Fracture-Plane Control Blasts with Satellite Holes

A novel fracture-plane control blasting technique with particular application in wall-control blasts in mines employing medium to large diameter boreholes is described. It consists of a string of nested holes, each nest consisting of a large diameter charge-hole flanked on either side by a small diameter satellite hole. Each nest is shown to be an analog of a pressurized hole with diametral notches along its length. This 'equivalent-notched' hole concept for generating controlled fractures along preferred directions has been successfully investigated in the laboratory and in the field. The technique has been used to generate controlled fractures on a quarry bench in highly jointed limestone. The resulting blasts with a 250 mm diameter central charge-hole and 50-75 mm satellite holes show that two nests of such holes almost 5 m apart could be joined by a single co-linear fracture. The design range of diameter ratio between charge-hole and satellite hole is 3 to 6 and spacing is 3 to 5 charge-hole radii. With careful matching of explosives and decoupling, and combination of diameter ratio and spacing, it would be possible to connect two nests of such holes more than 20 charge diameters apart by a single controlled fracture plane. The relative merits of the technique against existing wall-control blasts are discussed, and guidelines for practical fracture-plane control blast designs are discussed.
Return to parent product
  • Fracture-Plane Control Blasts with Satellite Holes
    PDF
    This product is exclusive to Digital library subscription
  • Fracture-Plane Control Blasts with Satellite Holes
    PDF
    Normal price $22.00
    Member price from $0.00
    Add to cart

    Fees above are GST inclusive

PD Hours
Approved activity
  • Published: 1990
  • PDF Size: 0.793 Mb.
  • Unique ID: P199005027

Our site uses cookies

We use these to improve your browser experience. By continuing to use the website you agree to the use of cookies.