The boulder, rock wall. bottom toe always appear in limestone mine mid deep bench blasting because of bedding, fault, joint and cave.
石灰石矿岩层较多，断层、节理裂隙和溶洞发育，爆破容易产生大块、岩墙和根底。
3
The results show that the failure of dam foundation is caused mainly by the extension of dam heel crack and the expansion of shear-yield zone of the foundation rock near the dam toe.