METHOD FOR PROTECTION OF STATIONARY CONSTRUCTIONS AGAINST NEGATIVE EFFECT OF SEISMIC ENERGY OF BLAST OPERATIONS AT IRON ORE ENTERPRISES

摘要

Method for protection of stationary constructions against negative effect of seismic energy of blast operations at iron-ore enterprises includes drilling in block rows of vertical main wells with diameter d and depth at distance between the rows of those wells and between the wells in the row, and the lengths of the rows that are equal, respectively, to H, h and L, with charging those and with short-delay firing. At that near the nearest to the construction protected of the row of main wells with diameter d, near each of those, at distance h, that is equal to (1.5-2.0)d, at the side opposite from the protected construction, one drills a row of additional inclined wells with same diameters d and depth , that is not less than 0.9H, at angle , equal to 45-55°, to horizontal plane, and in the opposite from the protected construction direction, in direction of vertical plane that goes through respective main well of the row and the nearest point of the protected construction one performs charging of all the wells and sequential short-delay firing of the charges of ES of all the rows of the wells. At that firing is started from the row of additional wells with formation in the massif between two rows of main wells that are most close to the protected construction, and by the whole length L of those of a continuous long depression, the side surfaces of that one serve as focusing, accumulating and guides of fluxes of seismic energy generated by explosions of the changes of ES of the rows of main wells in direction from the protected construction to continuous long depression with throwing out the broken mass from the construction out of the boundaries of the broken massif.