TY - CPAPER T1 - An extensional mechanism of instability and failure in the walls of open pit mines T2 - Slope 2013: 2013 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering AU - Bridges, MC ED - Dight, PM A2 - Dight, PM DA - 2013/09/25 PY - 2013 PB - Australian Centre for Geomechanics PP - Perth CY - Perth C1 - Perth SP - 137 EP - 150 AB - Evidence from studies of instability and failures in the walls of open pit mines and cuttings indicates a predominance of an extensional mechanism, comprising toppling, ravelling and creep-subsidence. This is interpreted to arise from relief and dilation when a pit wall is excavated, removing overburden and lateral confinement of the wall. Evidence does not support sliding and shear or shallow toppling mechanisms of instability or failure. UR - https://papers.acg.uwa.edu.au/p/1308_03_Bridges/ ER - DO - 10.36487/ACG_rep/1308_03_Bridges