I need to recover rocks for my prim 2

[nicmoffa]

I need to recover rocks for my primary seawall armouring.
Rocks have to be in the range of 1 cubic meter.
Mine site is in Australia - high content of iron and dolomite.
What recovery rate can be obtained from a blasting campaign?

 

[exploengineer]

Recovery of riprap for a seawall depends on the rock structure. The range can be as low as 1% to as high as 80%.

If you send me the local geology, I would be more then happy to give you a basic plan to start.

Frank

Frank Lucca

http://www.terradinamica.com

 

[nicmoffa]

Thanks Frank!

At this stage, sending the local Geology would be complicate (if you meant maps and Geolocical reports). However, I can say that the location appears to be a single solid bank with very little fracture. It contains Fe2O3 and Fe3O4.

Nic

 

[exploengineer]

Hi Nic,

No, that's what I meant.

If it is a pretty soild mass, you can use the following:

First, when making oversize, it is best to have the hole spacing smaller then the row burden.

Burden = 40 x charge diameter. Spacing = burden x .8

So, 115mm charge x 40 = 4.6m x .8 = 3.68m

Burden = 4.5m, spacing = 3.7m

Shoot at least 3 rows. Load the first row to normal height. Use a good bottom load to break to floor. Airdeck the rows behind row one. (load 80% of hole, stuff in a plug of some sort at about 12 x charge diameter and stem).

Many people will try and shoot 1 row. I've done this many times and have tried many techniques. This works the best. Expand and reduce pattern as needed to create right size. Also, you can play with the powder column height.

If you have any q's, I'll check back.

Frank

Frank Lucca

http://www.terradinamica.com

 

[nicmoffa]

Thanks Frank
I will let you know other details when we start the blasting program.

I wish you all the best and thanks again for you kindness

Nic