The invention relates to a construction method of a blasthole
stemming structure for drilling blasting and a concrete
block structure for the method. The blasthole
stemming structure comprises a cylindrical-conical reinforcement built-in concrete
block structure, a buffer section and a rock
ballast filling body meeting certain grain size requirements, wherein one end of the cylindrical-conical reinforcement built-in concrete
block structure is conical while the other end is cylindrical. After shock
waves formed after explosion of a blasting
cartridge pass the buffer section, concrete blocks on the blocking section generate velocity of movement towards the orifice direction under the action of the buffer section, the rock
ballast filling body is squeezed and generates
dislocation due to the wedging effect of the upper cone during movement so as to be squeezed and compacted, and bonding power and
friction force among particles increase sharply. Meanwhile, the rock
ballast filling body generates
lateral expansion, however, the squeezed and compacted rock ballast blocks the cylindrical-conical reinforcement built-in concrete block from rushing outwards due to the constraint effect of the hole wall, so that
detonation gas is effectively prevented from escaping from the blasthole, acting time of the
detonation gas on rock is prolonged, explosive energy is fully utilized, and blasting effect is enhanced.