What Is Bench Height In Mining

The elements of a bench are illustrated in fig.

What is bench height in mining.

In mining a bench is a narrow strip of land cut into the side of an open pit mine. Open pit mining bench height multi criteria decision making. Determination of optimum bench height is a major concern in most open pit mines. 1 5 bench height the bench height is the vertical distance between each horizontal level of the pit.

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. For large mines it is on the order of 12 to 15 metres about 40 to 50 feet. This subject has always been an issue with different and sometimes conflicting criteria that have to be. Introduction as a definition in open pit mining bench height is the vertical distance between crest and toe of the bench fourie and dohm 1992.

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. These step like zones are created along the walls of an open pit mine for access and mining. The thickness that is the height of the benches depends on the type of deposit the mineral being mined and the equipment being used. 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.

However for 20 m of bench height because of the increase in priming the unit cost tends to build up increase. Unless geological conditions dictate otherwise all benches should have the same height. Harraz presentation mining methods surface mining 23. 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.

It s possible to drill the intermediate bench trim row closer to the toe of the. Bench height has been found to be 15 m. Determination of practical bench height is an important subject in open pit mining. As the bench height goes up unit cost appears to drop.

Mining is generally conducted on a number of benches at any one time. At the same time the blast unit cost has been seen to diminish as the hole diameter grows.