Roof And Pillar Mining

The most common mining system is room and pillar.

Roof and pillar mining.

Room and pillar is an underground mining method that has applications to a wide variety of hard rock deposits worldwide. In the northeast edge of antaibao surface mine were jingyang coal mine shallow mined out areas exploited by the room and pillar mining method. Pillar and roof span stability are two essential prerequisites for safe working conditions in room and pillar mines. When the distance between connecting drifts is the same as that between the parallel drifts then a.

In this system a series of parallel drifts are driven with connections made between these drifts at regular intervals. To do this rooms of ore are dug out while pillars of untouched material are left to support the roof overburden calculating the size shape and position of pillars is a complicated procedure and is an area of. It is commonly classified as an open stoping method meaning that development involves mining out underground cavities while leaving the surrounding un mined waste or ore as primary support. The conventional calculation formulas and conditional thickness meth ods were used to determine the room and pillar mining system parameters which guarantee a long term stability.

Since the rock roof of shallow mined out areas was easily weathered the stratified rock roof would distort and decline and roof failure would occur under the gravity and the overlying strata load with the passage of time. Unstable pillars can result in rock sloughing from the pillar and can lead to the collapse of the roof if one or more pillars should fail.