On April 30, 1999 an estimated 10,300 square meters of roof area collapsed at the Moonee Colliery longwall coal mine near Sydney, Australia. The collapse itself was not the problem, longwall coal mines are nearly always designed such that stabilization occurs through frequent caving events in the mined-out region behind the longwall face. The problem was that it occurred on a very large scale and without warning. A miner was injured when he was thrown by the resulting wind blast, and the mine was... Mehr
Preis-Alarm
