摘要
为研究高地应力下爆破荷载和动态卸载效应对破岩效果和损伤破坏范围的影响,在理论上分析了在爆破荷载和动态卸载作用下裂隙区和弹性区岩石应力分布和破裂特征。基于断裂力学和可释放应变能的岩石损伤破坏准则计算了岩石破碎块度d和岩石损伤破坏范围Rd。计算结果表明,当初始地应力达到50 MPa以上,炮孔半径为42 mm,2号岩石改性铵油炸药耦合装药起爆后原岩中积聚的弹性应变能释放后可以达到裂隙区破碎能的16%以上。高地应力卸载后在爆腔腔壁将产生一个径向拉应力,在裂隙区边缘拉应力为2 MPa,最大拉伸位移为0.24 mm,在弹性区由于卸载径向拉伸应力的作用促使其聚积的应变能沿径向释放,使弹性区形成新的损伤破坏,损伤破坏区厚度为0.03 m。随着爆腔半径和裂隙区半径的增大,动态卸载释放的能量和损伤破坏区的厚度也将随之增大。
In order to study influences of dynamic unloading effect and blasting load under high earth stress on rock breaking effect and damage zone,rock stress distribution and fragmentation characteristics of crack zone and elastic one under blasting load and dynamic unloading wave were theoretically analyzed. The rock fragment size d and rock damage range Rd were calculated based on the fracture mechanics and the damage failure criterion for rock being able to release strain energy. The calculation results showed that when the initial earth stress reaches larger than 50 MPa and the blast hole radius is 42 mm,the released strain energy in 2# rock under the dynamic unloading can reach more than 16% of rock breaking energy in crack zone; after high earth stress is unloaded,the blast hole wall produces a radial tensile stress,it is2 MPa at the edge of fracture zone and the maximum tensile displacement is 0. 24 mm; in elastic zone,the strain energy releases along the radial direction under the action of radial tensile stress caused by dynamic unloading,a new damage zone is formed in elastic zone and its thickness is 0. 03 m; with increase in blast hole radius and crack zone one,the released energy under the dynamic unloading and the thickness of the damage zone in elastic zone are also enlarged.
作者
肖思友
姜元俊
刘志祥
苏立君
XIAO Siyou1,2,3, JIANG Yuanjun1 ,2 , LIU Zhixiang3 , SU Lijun1,2,4(1. Key Lab of Mountain Hazards and Earth Surface Processes, Chinese Academy of Sciences, Chengdu 610064, China; 2. University of Chinese Academy of Sciences, Beijing 100049, China; 3. School of Resources and Safety Engineering, Central South University, Changsha 410083, China; 4. CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, Chin)
出处
《振动与冲击》
EI
CSCD
北大核心
2018年第15期143-149,共7页
Journal of Vibration and Shock
基金
国家重点基础研究发展计划(2013CB733201)
国家自然科学基金(51674288)
中科院"百人计划"(苏立君)
关键词
高应力
爆炸能量
动态卸载
断裂
应变能释放
损伤破坏
high earth stress
blasting energy
dynamic unloading
fracture
strain energy releasing
damage failure
