世界核地质科学2025，Vol.42Issue(6)：1322-1332,11.DOI:10.3969/j.issn.1672-0636.2025.06.015
北山花岗岩爆破损伤及力学特性劣化研究
Study on blasting damage and mechanical property degradation of Beishan granite
摘要
Abstract
Blasting excavation induces microcracks inside the surrounding rock,forming an excavation damaged zone(EDZ)and deteriorating the mechanical properties of the rock mass,which affects the stability of the tunnel.To determine the depth and damage degree of the blasting-induced excavation damaged zone,this study takes the blasting excavation of the entrance section of the spiral ramp in the Beishan Underground Laboratory—China's first underground laboratory for high-level radioactive waste geological disposal—as the research object.The P-wave velocity measurement is adopted to systematically obtain the wave velocity change rate η,delineate the blasting excavation damaged zone,and fit the blasting damage quantification model.Combined with the Hoek-Brown criterion,the degraded mechanical parameters of the rock mass in the blasting damaged zone of the ramp entrance section are derived,and the reference values of the degraded rock mass mechanical parameters under different Geological Strength Index(GSI)conditions are provided.The main research results show that:1)The Beishan granite is dense,and the damage caused by blasting waves attenuates rapidly;based on the wave velocity change rate η,the blasting damage depth is effectively delineated as 22.8 cm,and the maximum wave velocity change rate induced by blasting reaches 39.05%;2)Through the rock damage degree parameter D,the spatial distribution characteristics of surrounding rock damage caused by blasting impact are clarified,with the maximum rock damage degree induced by blasting being 0.63;3)Combined with the Hoek-Brown criterion,the degraded mechanical parameters of the surrounding rock after blasting excavation are determined,where the elastic modulus Em,cohesion c,and internal friction angle φ are 34.20 GPa,5.37 MPa,and 61.44 °,respectively;4)An interpolation table of the degraded rock mass mechanical parameters after blasting excavation under different Geological Strength Index conditions is provided,which offers reference data for the rapid stability analysis and support suggestions of the blasting-excavated tunnels in the subsequent Beishan Underground Laboratory.The research results have important guiding value for the safety assessment of high-level radioactive waste geological disposal projects.关键词
高放废物地质处置/爆破开挖/波速测试法/围岩损伤/岩体力学参数Key words
geological disposal of high-level radioactive waste/blasting excavation/rock damage/P-wave velocity measurement/rock mass mechanical parameters分类
建筑与水利引用本文复制引用
ZHENG Yiwu,WU Shibing,CHEN Liang,ZHAO Xingguang..北山花岗岩爆破损伤及力学特性劣化研究[J].世界核地质科学,2025,42(6):1322-1332,11.基金项目
中国国家原子能机构核设施退役治理专项(编号:科工二司[2020]194号)资助 Supported by China Atomic Energy Authority of China Special Fund for Decommissioning of Nuclear Facilities Research Project Science and Industry Division(No.科工二司[2020]194) （编号:科工二司[2020]194号）
