摘要
为探究冻结岩体的冲击力学性能,并提出寒区爆破开挖工程中合理的爆破炸药单耗,针对寒区典型分布的砂岩,采用室内分离式霍普金森压杆试验与理论分析相结合的方法,开展了冻结砂岩冲击力学性能及爆破破岩能量耗散特性研究。结果表明:(1)冻结状态砂岩的动态抗压强度和动态弹性模量相比常温状态整体有所提升,而应变峰值整体有所下降。对比静载与动载试验结果,相同物理参数下,砂岩的抗压强度差距不大,而动态弹性模量明显高于静态弹性模量。(2)常温状态砂岩和冻结状态砂岩试件的耗散能量均随含水率的增大而逐渐减低,且冻结状态砂岩的耗散能量高于常温状态。相比常温状态,冻结砂岩在含水率为0、0.25ω、0.50ω、0.75ω、1.00ω时,其耗散能量增幅分别为21.6%、64.9%、80.3%、78.2%、83.3%。(3)相同含水率下,冻结状态砂岩的炸药单耗均高于常温状态,在含水率为0、0.25ω、0.50ω、0.75ω、1.00ω时,冻结状态砂岩爆破炸药单耗相比常温状态分别增加20.4%、61.3%、60.0%、55.6%、66.7%。(4)将常温与冻结状态砂岩爆破炸药单耗数值进行拟合,得到不同状态砂岩爆破破岩的单耗修正模型,可为寒区爆破工程提供参考。
Typical sandstones distributed in cold regions were chosen as the research object to study the impact mechanical properties of frozen rock mass and provide reasonable unit explosive consumption for frozen rock mass in blasting excavation engineering in cold regions.Sandstone specimens with different moisture contents were prepared by the controlled mass method.Comprehensive research methods of indoor split Hopkinson pressure bar(SHPB)test and theoretical analysis are used to study the impact mechanical properties and blasting fragmentation energy dissipation characteristics of frozen sandstones.The results are as follows.(1)The dynamic compressive strength and dynamic elastic modulus of frozen sandstone are overall improved compared to the room temperature state,while the peak strain is generally decreased.Comparing the dynamic and static load test results of the mechanical properties of sandstone,the difference between the compressive strength of sandstones with the same physical parameters under dynamic and static loads is small,and the dynamic elastic modulus is significantly higher than the static elastic modulus. (2) The energy dissipation of room-temperature and frozen sandstone specimens decreases gradually with the increase of moisture content, and the energy dissipation of frozen sandstone is higher than that at room temperature. Under the moisture content of 0, 0.25ω, 0.50ω, 0.75ω, and 1.00ω, the energy dissipation of frozen sandstone increased by 21.6%, 64.9%, 80.3%, 78.2%, and 83.3%, respectively compared with the room temperature state. (3) The unit explosive consumption of frozen sandstone with the same moisture content is higher than that at room temperature, with moisture contents of 0, 0.25ω, 0.50ω, 0.75ω and 1.00ω, the unit explosive consumption of sandstone in the frozen state is 20.4%, 61.3%, 60.0%, 55.6%, and 66.7% higher than that in room temperature state. (4) By fitting the unit explosive consumption values of sandstone at room temperature and frozen state, a correction model for t
作者
蒋楠
张硕彦
姚颖康
周传波
罗学东
曹华彰
JIANG Nan;ZHANG Shuoyan;YAO Yingkang;ZHOU Chuanbo;LUO Xuedong;CAO Huazhang(State Key Laboratory of Precision Blasting,Jianghan University,Wuhan 430056,Hubei,China;Hubei Key Laboratory of Blasting Engineering,Jianghan University,Wuhan 430056,Hubei,China;Faculty of Engineering,China University of Geosciences,Wuhan 430074,Hubei,China)
出处
《爆炸与冲击》
EI
CAS
CSCD
北大核心
2024年第5期140-155,共16页
Explosion and Shock Waves
基金
国家自然科学基金(41972286,42072309,42102329)
江汉大学省部共建精细爆破国家重点实验室、江汉大学爆破工程湖北省重点实验室联合开放基金(PBSKL2023A1)。
关键词
冻结岩体
动力冲击
爆破破岩
能量耗散
炸药单耗
frozen rock
dynamic impact
blasting fragmentation
energy dissipation
unit explosive consumption
