• BLASTING
  • Vol. 38, Issue 2, 58 (2021)
ZHOU Hai-xiao1、*, GAO Qi-dong1, WANG Ya-qiong1, LENG Zhen-dong2, and CHEN Ming3
Author Affiliations
  • 1[in Chinese]
  • 2[in Chinese]
  • 3[in Chinese]
  • show less
    DOI: 10.3963/j.issn.1001-487x.2021.02.009 Cite this Article
    ZHOU Hai-xiao, GAO Qi-dong, WANG Ya-qiong, LENG Zhen-dong, CHEN Ming. Comparative Study of Vibration Induced by Presplitting Blast-holes and Main Blast-holes During Extension of Hydropower Station[J]. BLASTING, 2021, 38(2): 58 Copy Citation Text show less

    Abstract

    On the background of the extension of Nam Ngum 1 Hydropower Station in Laos, the blast vibration tracking of the existed buildings and equipment was implemented.The vibration characteristics of presplitting blast-holes and main blast-holes were compared by analyzing the statistical data.Besides, the smoothed particle hydrodynamics(SPH) numerical technique was used to study the causes of the vibration differences induced by presplitting blast-holes and main blast-holes from the views of charging structures, initiation modes and burden sizes.Results indicate that the peak particle velocity(PPV) induced by presplitting blast-holes is generally higher than that induced by main blast-holes.The charging structures, initiation modes and burden sizes all play a significant role on the explosion loading characteristics as well as the evolution and distribution of the nearfield blast damage, which further affects the transmission and distribution of explosion energy.The explosives in presplitting blast-holes are generally decoupled charging with the rock mass and laterally initiated by the detonating cord.Moreover, the burden of presplitting blast-holes is always larger than that of main blast-holes.The peak blasting pressure on presplitting blast-hole walls is lower than that on main blast-hole walls.For the presplitting blast-holes, the crush zone and the number of cracks adjacent to the blast-hole, as well as the damage degree of the rock mass along the resistance direction, are all relative smaller.Thus, less explosion energy is consumed by rock fragmentation and throwing, allowing more energy to be converted into vibration energy.Consequently, the vibration induced by presplitting blast-holes is relative larger than that induced by main blast-holes.
    ZHOU Hai-xiao, GAO Qi-dong, WANG Ya-qiong, LENG Zhen-dong, CHEN Ming. Comparative Study of Vibration Induced by Presplitting Blast-holes and Main Blast-holes During Extension of Hydropower Station[J]. BLASTING, 2021, 38(2): 58
    Download Citation