摘要
为揭示露天矿山冻土层在爆破荷载冲击下的破断规律,阐明冻土层爆破大块产生的原因,通过室内力学试验分析冻土的抗拉强度和抗压强度与温度间的动态关系,结合悬臂梁力学理论,建立爆炸荷载作用下冻土层破断简化悬臂梁模型,得到冻土层破断长度的理论计算公式,提出深、浅孔组合爆破技术,在甲玛铜矿开展实际应用。研究结果和现场应用表明:冻土的抗拉强度和抗压强度均随温度的降低而升高;在爆破过程中冻土层与下方岩层产生分离,冻土层形成悬臂梁结构,冻土层在悬臂梁结构的最大弯矩处断裂,随着土体温度持续降低,冻土层破断长度逐渐增大。成功在西藏甲玛矿区应用,将冻土层大块率控制在4%以内,有效减少了冻土层大块的产生。
In order to reveal the breaking rule of frozen soil layer in open-pit mines under the impact of blasting load and clarify the reasons for the occurrence of large blasting blocks in frozen soil layer,the dynamic relationship between the tensile strength and compressive strength of frozen soil and temperature is analyzed through indoor mechanical tests.Combined with the cantilever beam theory,a simplified cantilever beam model for the breaking of frozen soil layer under explosive load is established,the theoretical calculation formula for the breaking length of frozen soil layer is obtained.The practical application in Jiama copper mine shows that the tensile strength and compressive strength of frozen soil increase with the decrease of temperature.During the blasting process,the frozen soil layer is separated from the rock layer below,and the frozen soil layer breaks at the maximum bending moment of the cantilever beam structure.With the continuous decrease of the soil temperature,the breaking length of the frozen soil layer gradually increases.It has been successfully applied in Jiama mining area of Tibet,controlling the rate of frozen soil mass within 4%,effectively reducing the generation of frozen soil mass.
作者
全铭
杨旭升
胡智航
王雪松
徐振洋
QUAN Ming;YANG Xusheng;HU Zhihang;WANG Xuesong;XU Zhenyang(School of Mining Engineering,University of Science and Technology Liaoning,Anshan 114051,China;Engineering and Technology Research Center of High-Efficiency Mining-Processing and Utilization of Metal Mineral Resources,Anshan 114051,China;Chengyuan Mining Co.,Ltd.,Liaoyang 111000,China;School of Architecture and Civil Engineering,Shenyang University of Technology,Shenyang 110870,China)
出处
《有色金属工程》
CAS
北大核心
2023年第2期139-148,共10页
Nonferrous Metals Engineering
基金
“十三五”国家重点研发计划资助项目(2016YFC0801603)
国家自然科学基金资助项目(51974187)
辽宁省教育厅重点项目(LJKZ0282)。
关键词
露天矿山
超高海拔
冻土爆破
大块率
open pit mine
ultra high altitude
frozen soil blasting
block rate
