Strategy considering exact lithology shipment
Undergoing stone blasting, the fresh bodily and you can mechanical attributes of your own stone is actually surely you to definitely of your own head activities you to influence the end result of material blasting 21 . There is will an unclear understanding that the fresh more challenging new stone, this new more challenging it’s as blasted in the present technology industry. Yet not, the new blasting feeling isn’t exactly as questioned for the engineering practices. Alternatively, it has been learned that brand new hardness regarding stone isn’t highest since the unit consumption of explosives is actually high 22 .
According to cracking process out of material blasting 23 , the power released by explosives acts on rocks by the shock trend and you will extension stress out of detonation fuel whenever an explosive explodes with the stones. A perfect destruction from rocks is due to the action be concerned developed by the brand new rush exceeding their stamina restriction, and this indicates that the latest crushing state is closely pertaining to new rush time and mechanized features of stone. To put it differently, within the specific standards regarding equipment volatile practices mode, style of, and free surface, the new charge numbers is certainly caused by influenced by the new physical attributes off stone to achieve a specific smashing impression. Therefore, brand new lithology shipment is the number 1 basis for choosing new product consumption of explosives twenty four .
When you look at the an out in-breadth study of the new lithology regarding hard rock, it is learned that large stress keeps a critical impact on the new blasting techniques and you may rock breaking perception. The outcome including show that higher-site fret unloading and you may blasting loading aren’t two independent process, to the contrary, it works from inside the assistance, and the active unloading provides a life threatening effect twenty five . Thus, the brand new delivery from hard rock is the vital thing on the structure from an excellent segmented costs for blasthole.
Grouping off blasthole rock strata
Throughout the traditional blasting techniques, the brand new lithology difference across the great time opening breadth isn’t experienced from the blasting design. Ergo, one charges build is actually then followed. About superimposed stone size that have silky and difficult inclusions, the brand new weakened interlayer’s compression and you will tensile resistance stamina are lowest compared to one to regarding cutting-edge rock structures, almost minimal. At the time, brand new weak interlayer can simply get to be the flood station of your own detonation gas and weaken this new smashing Rochester backpage female escort and you may organizing aftereffect of the fresh high-pressure fuel generated by the rush. Additionally, regarding large hard rock instead of rush cracks, it’s difficult to crack sizeable rocks using the additional smashing principle off cut off material crash throughout the putting techniques owed so you’re able to a failing interlayer 26 . Hence, the fresh new section off soft-rock and hard stone is an essential action of the framework approach.
The lithology data of the corresponding blastholes are obtained by intelligent drilling rigs. According to the hardness of the lithology, the blasthole rock strata are divided into 7 categories, and lithology classification numbers range from Type 1 to Type 7 27 . In order to facilitate the design and calculation of blasthole charge structure, the adjacent strata with similar lithology are combined and grouped. The lithology is divided into two groups of soft rock and hard rock, denoted as \(s\) and \(h\) , respectively. The classification rule of soft rock and hard rock is that the strata numbered 1, 2, 3, and 4 are soft rocks, and rock strata numbered 5, 6, and 7 are hard rocks. The grouping diagram of blasthole rock strata is shown in Fig. 4: H refers to the blasthole depth, Rs means the thickness of soft rock, and Rh means the thickness of hard rock.
