LAUSR

Anguran Lead and Zinc Mine is the largest lead and zinc mine in Iran and the Middle East. In 2006, the north-west wall of this mine had an enormous collapse (approximately 30 million tons). Concerns about another collapse of this wall is more than before with the increasing depth of the ore deposit nowadays. Therefore, the mine development program for excavation the whole of ore deposit, needs to ensure stabilization of the NW wall. In the current research, to estimate weathered depth and probable collapses of the NW wall, the flat dilatometer in situ test (DMT) was used. The flat dilatometer test had the lowest distortions caused by the penetration in the surroundings formations, due to its ground insertion methods without needing borehole drilling. Using this test, it was possible to identify relaxation zones and collapsible zones. Depth of weathered zone was determined 0.5–2 m in the foot of bench and the whole of this weathered zone was distressed by the DMT analyzed data. The whole of landslides were identify surface active and didn’t identify quiescent slip surface in this zone.