What Is Bench Height In Mining

The elements of a bench are illustrated in fig.

What is bench height in mining.

Stiffness ratio bh b where bh is bench height b is the burden target stiffness ratios 3 to 4 is normal range 4 does not improve fragmentation may risk cut offs much above 6 2 redesign if you can 2 get someone you dont like near shot stiffness ratio example. In mining a bench is a narrow strip of land cut into the side of an open pit mine. Opencast working method of opencast working bench bench height bench width and bench slope angle provision regarding bench height bench width and bench slope angle bord and pillar method video. However for 20 m of bench height because of the increase in priming the unit cost tends to build up increase.

At the same time the blast unit cost has been seen to diminish as the hole diameter grows. Bench height has been found to be 15 m. Raised beach also known as marine terrace a beach or wave cut platform raised above the shoreline by a relative fall in the sea level. Mining is generally conducted on a number of benches at any one time.

The thickness that is the height of the benches depends on the type of deposit the mineral being mined and the equipment being used. Determination of practical bench height is an important subject in open pit mining. These step like zones are created along the walls of an open pit mine for access and mining. Open pit mining bench height multi criteria decision making.

1 5 bench height the bench height is the vertical distance between each horizontal level of the pit. Mining was conducted with a cat 5130 excavator cat 994 and 992 loaders matched with cat 777 haul trucks. Determination of optimum bench height is a major concern in most open pit mines. Harraz presentation mining methods surface mining 23.

Diagram it can be seen that the single bench height was 15m with a drill offset on the intermediate bench of between 5 6m from the toe of the upper bench. What is the stiffness ratio for a 40 foot bench with 6 5 feet of burden on each hole 40 6 5 6 15 shot. 2 february 2016 prof. This subject has always been an issue with different and sometimes conflicting criteria that have to be.

It s possible to drill the intermediate bench trim row closer to the toe of the. As the bench height goes up unit cost appears to drop.