RU97100449A - EXPLOSION METHOD - Google Patents

Claims (2)

1. The method of blasting, including preliminary weakening of the rock mass by drilling additional blast holes, loading them with explosives and short-blast blasting with a certain delay, characterized in that the front of the ledge is oriented subparallel to the main axis of the anisotropy of the massif, it is divided into separate blasting blocks , they drill and blow odd blocks first, and then even blocks, while groups of borehole charges of odd blocks are blown in transverse rows, starting from the middle s of each block, the first to explode with a zero degree of deceleration, a group of charges on the central odd block, the subsequent groups of charges of odd blocks explode with a deceleration interval t _i equal to
t _i = l _{(i, i-1)} / C _pi , s,
where l _{(i, i-1)} is the distance between the i-th and previous groups of charges, m;
C _pi is the longitudinal wave propagation velocity between the i-th and i-1st groups of charges at the time of initiation of the i-th group of charges, m / s. 2. The method according to p. 1, characterized in that the length of the even blocks L is determined by the formula:
L = (0.5-0.8) K _p α (Q $\genfrac{}{}{0ex}{}{\text{1/3}}{\text{1}}$ + Q $\genfrac{}{}{0ex}{}{\text{1/3}}{\text{2}}$ ),
where K _p - coefficient of rock properties, m / kg ^1/3 ;
α is the coefficient of explosion conditions;
Q ₁ , Q ₂ - mass of explosive charges in groups of charges exploded in odd blocks, kg ^1/3 .