1. Control the depth of the blasthole and reduce the height of the step According to the mining design, the 12-meter step arrangement, the vertical hole, and the blast hole depth of 13 meters for blasting operations, the vibration generated by the blasting is quite obvious, and the houses around the mine are damaged by the blasting seismic waves. When the 8m step is used, the impact of the blasting seismic wave is weak when the depth of the blasthole is 9 meters, and it has no effect on the residential building. 2, select a small bore rig , reduce the hole distance and row spacing When the blasthole with a hole diameter of 150cm is used, the vibration generated by the blasting has obvious influence. When the blast hole with a hole diameter of 100cm is used, the vibration is obviously reduced, and the safety requirement can be achieved. 3. Limit the total charge per blasting When the total charge of blasting exceeds 1 ton, the blasting seismic wave is more obvious. When the total charge is less than 1 ton, the impact is within an acceptable range and will not cause damage to the houses. 4. Limit the amount of explosives in each section and increase the number of detonators When the amount of explosives detonated by each detonator exceeds 250 kg, the vibration increases significantly. Therefore, we increase the number of detonators and control the amount of charge per section to minimize the impact of seismic waves generated by the blast on nearby villages. 5. Strictly control and adjust the charge of each gun hole according to the nature of the rock Due to the complex nature of the ore rock, cracks, fracture zones, karst caves and other serious interference with the effect of blasting, the blasting technicians should follow the whole process to track the eye, timely grasp the specific situation of each blasthole, and determine the change of the ore properties according to the blasthole. Charge amount. 6, can only use loose blasting technology Because the minimum distance from the village is only 200 meters, the blasting technology we have at present can only use the medium-deep hole step loose control blasting to minimize the impact of blasting flying stones and prevent the villagers from causing damage caused by blasting flying stones. 7. No secondary blasting should be used to decompose large ore. According to the special situation mentioned above, we must not use the method of blasting to decompose large ore, and the large ore is decomposed by gun. 8, each row of blastholes should try to use segmental detonation Due to the arrangement of multiple rows of blastholes, if the blasting network adopts a row of detonation, the amount of explosives in a certain burst is still large, and the free surface of the blasting is relatively small. If each row of blastholes is detonated in sections, the number of detonator segments required is larger, thereby reducing The amount of explosives detonated in each section also greatly increases the free surface of the blasthole that is detonated in the future, and the blasting effect is obvious, and the vibration generated by the blasting is also effectively controlled. 9, the rear row of blastholes must use segmental detonation The rear blastholes are simultaneously detonated, and the back thrust generated is quite large. The impact of seismic waves is obvious, which will cause serious damage to the houses. If more than 8 blastholes are detonated in the same section of the rear row, a strong seismic wave will be generated, so the rear blastholes are the same. Segment detonation should be controlled below 6 blastholes. 10. Fully consider the free surface of each blasthole blasting Since the free surface of the blasthole is more, the number of seismic waves generated during blasting is less, so it should be considered in each blast design. If the blasting face is allowed, the blasthole should have as large a free surface as possible. Fulike Houseware&Gifts Co.,Ltd. , https://www.cnfulike.com
Safety technical measures for open pit mine blasting near villages
The biggest blasting technical problem facing the open pit mine near the village group is blasting vibration and flying stone. In the current conventional blasting, the blasting flying stone should be effectively controlled, but the impact of blasting vibration needs further research and resolution. Here we will Some problems encountered in practice suggest some solutions for reference.