Rock Machanics & Quarrying:

[nurhforward]

My kind greetings,
I visited a quarry site;precisely my Company quarry - Gitto Quarry Project LTD. The activities going on site includes: rock drilling (12-18m depth) using a rock drilling wagon; rock blasting/burst; stockpiling of rock debris; hualage etc.

On inspection, I discovered that the sizes of drill (50mm) and the type of explosives being used had a significant effects on the rock debris when compared with similar rock debris obtained from a near-by construction site running a quarry (BULLETINE).

The major differences were the sizes of the debris; the naturral strenght of the gravel (AIV); the physical texture and fabrics of rocks obtained from two different quarry site.

To this end, I like to know more on quarrying and rock machanics; since rock machanics as specailised branch of geotechnical engineering keep advancing everyday...

My kind regards, pls.



nurhforward, Gitto International.

 

[DRC1]

Blasting is more of an art tha a science. Generally a section of the wall is blasted free from the face by means of presplitting. Presplitting is a line of closely drilled holes lightly to modertely loaded. Larger holes drilled within the mass are drilled and loaded and generaly broken from the center out. All the blasts are set off at the same time and controled by delays. the entire blast is completed within a few milliseconds. The size of the rock can be adjusted by changing the patteren, the load or both. How the material breaks is a function of the rock.