Help with terminology please

[roo.walters.4]

Hi there folks... might any mining enthusiast help me with the meaning of some mining terms please...

Breaking Line
Free face
Interburden

Thanks

[aricooperdavis]

I can help with "interburden" which is the material that separates the seams/veins/beds that you are trying to mine, generally vertically. The terminology is similar to the "overburden" which is the material above what you're trying to mine, so the burden of material that needs to be removed if you're working down from the surface.

[alastairgott]

I have checked a few websites using google for reference to "free face" or "breaking line" (the websites were: PDMHS, Namho and Aditnow)

The only "hit" I got was on a topic of Shotholes from Aditnow where "free face" was used on 11/11/11 by mr.c https://www.aditnow.co.uk/community/viewtopic.aspx?p=88541#msg88550

Yorkshireman wrote:


Could an intentionally shaped hole have been a forerunner of shaped charges?

Not realy, apart from insomuch as you are directing a line of fracture.
The shaped charge (Munroe effect) sort of works by focusing the detonation wave upon a particular point. The charge requires a stand off from the "burden" & in solid rock is pretty ineffective, in rather the same way as an adobe charge is - it needs a free face opposite the charge in order to work. Also you need an explosive with a high VOD and density (ie high brissance)- blasting gelatine having the lowest brissance (that I know of) that reliablely is used in such a way. Black powder certainly would not normaly suit the bill.

Not sure if this answers your question but also seems to refer to Burdens?

If you could use "Breaking line" in a sentence then some bright spark might have an answer.

[pwhole]

I'm only guessing, but maybe 'breaking line' is literally the arc of charges outlined on the face before blasting? I'm sue TPot can help here

[mikem]

Breaking line is the line that the block will split along, whether you're using charges or wedges.

Free face is the direction the rock moves in order to split it from the bed - if you have a series of charges then the free face may be the breaking line of the previous block, rather than an exposed face, but the outer one will be exposed.