激光照射花岗岩抗拉强度及孔隙分布研究
Experimental study on tensile strength and pore distribution of granite by laser irradiation
吴波 1刘林 1郁东旭 2王建州 2王义江2
作者信息
- 1. 江西赣禹工程建设有限公司,江西南昌 330038
- 2. 深地科学与工程云龙湖实验室,江苏徐州 221116;中国矿业大学深地工程智能建造与健康运维全国重点实验室,江苏徐州 221116
- 折叠
摘要
激光辅助破岩技术有助于提高超硬、超深地层资源的开采效率.采用控制变量法开展了激光热裂花岗岩试验,分析了温度、射孔参数、比能、热裂效能、抗拉强度和孔隙分布等变化规律.结果表明,激光照射下花岗岩表面温度超过1 000 ℃;花岗岩射孔直径、深度和射孔速率随照射参数呈非线性变化,最大射孔直径、深度和速率分别为10.0 mm、12.0 mm和2.70 mm/s;花岗岩最大比能和热裂效能分别为87.8 kJ/cm3和39.5 kJ/cm3.激光照射后花岗岩单轴破坏模式为脆性破坏,抗拉强度最大降幅为74.11％.激光照射导致岩石内部中小孔隙连通形成大孔隙,并最终导致岩石断裂.
Abstract
Laser-assisted rock-breaking technology contributes to enhance the mining efficiency of re-sources in ultra-hard and ultra-deep formations.A laser thermal cracking test on granite is carried out using the controlled variable method,and the changing rules of radial temperature,borehole parame-ters,specific energy,thermal-cracking energy,tensile strength and pore distribution were researched.The results reveal that the temperature of granite surface under laser action is more than 1 000 ℃,and the diameter,depth and rate of granite perforation vary nonlinearly with the irradiation parameters,and the maximum diameter,depth and rate of perforation are 10.0 mm,12.0 mm and 2.70 mm/s.The maximum specific energy and thermal-cracking energy of granite are 87.8 kJ/cm3 and 39.5 kJ/cm3,re-spectively.The damage pattern of granite is brittle fracture after laser irradiation,and the maximum decrease of tensile strength is 74.11％.The large pores generate under laser action by connecting of small and medium-sized pores in the rock,which ultimately results in the fracture of the rock.
关键词
激光辅助破岩/温度分布/热裂效能/抗拉强度/核磁共振Key words
laser-assisted rock-fracturing/temperature distribution/thermal-cracking energy/tensile str-ength/nuclear magnetic resonance引用本文复制引用
基金项目
深地科学与工程云龙湖实验室重点攻关项目(104023006)
出版年
2024
NETL
NSTL
万方数据