Blasting is still unavoidable in ore extraction, hence the process of mining is interrupted. Therefore, the maximum concentration of mining both in time and space, characteristic of modern mining, with the use of efficient mining systems and productive self-propelled equipment is especially important. The experience of domestic mining practice and conducted research, as well as the exchange of views at the V International Mining Congress held in Moscow in 1967 make it possible to outline some solutions in terms of directions for the development of technology of underground development of ore deposits.

At two-stage development of powerful steeply falling deposits with replacement of inter-chamber ore pillars with concrete wall supports it is very important to choose the right wall thickness and concrete grade. The methodology of such calculations is insufficiently covered in mining engineering literature. Laboratory studies on models at the Leningrad Mining Institute have shown that inter-chamber concrete supports in mining systems with ore storage or under-storey stripping (with subsequent filling of chambers with stockpiles) resist lateral loads like thin slabs with different fixing along the contour. The final destruction of the wall under the action of lateral loading occurs from the loss of stability by overturning or shear (wall subsidence).