摘要
胶结充填体作为人工矿柱,在地下爆破开采中经常受到冲击荷载作用,其稳定性受到严重影响。基于RHT(Riedel-Hiermaier-Thoma)损伤本构模型,利用ANSYS/LS-DYNA软件开展不同冲击速率(2、3、4、5 m/s)下不同灰砂比(1∶4、1∶6、1∶8)胶结充填体的SHPB动态冲击数值模拟试验研究,探讨胶结充填体动态抗压强度、强度增长因子、吸收能与冲击速率之间的关系,阐明胶结充填体动态破坏模式及破坏过程。研究结果表明:①胶结充填体试件的动态抗压强度、动态强度增长因子均随冲击速率增加而增大,且相同冲击速率下灰砂比越高,胶结充填体的动态抗压强度越大,但动态强度增长因子越小;②胶结充填体吸收能随着冲击速率增加而逐渐递增,呈线性增长趋势,且灰砂比越高吸收能增长越快;胶结充填体破坏过程表现为试件端部首先出现损伤,轴向、横向裂纹依次出现,裂纹扩展直至贯穿并向内部发展,最终完全破坏,失去承载能力;③以上结论同时验证了RHT模型参数取值的准确性,RHT损伤本构模型的成功应用,为开展胶结充填体动力学特性相关数值研究提供了参考。
As an artificial pillar,the cemented backfill is often subjected to impact loads during underground blasting mining,which seriously affects its stability.Based on the RHT(Riedel Heirmaier Thoma)damage constitutive model,ANSYS/LS-DYNA software was used to conduct SHPB dynamic impact numerical simulation experiments on the cemented backfill with different lime sand ratio(1∶4,1∶6,1∶8)at different impact rates(2,3,4,5 m/s).The relationship between dynamic compressive strength,strength growth factor,absorption energy,and impact rate of the cemented backfill is explored,and the dynamic failure mode and process of the cemented backfill is analyzed.The study results show that:①The dynamic compressive strength and dynamic strength growth factor of the cemented backfill increase with impact rate,and the higher the lime sand ratio at the same impact rate,the greater the dynamic compressive strength of the cemented backfill,but the dynamic strength growth factor is actually smaller.②The absorption energy of the cemented backfill gradually increases with impact rate,showing a linear growth trend,and the higher the lime sand ratio,the faster the absorption energy growth.The failure process of the cemented backfill is manifested as the first occurrence of damage at the end of the specimen,followed by axial and transverse cracks that propagate until they penetrate and develop inward,ultimately leading to complete failure and loss of load-bearing capacity.③The above conclusions also verify the accuracy of the RHT model parameter values,and the successful application of the RHT damage constitutive model provides a reference for subsequent conducting numerical research on the dynamic characteristics of the cemented backfill.
作者
程爱平
李鑫鹏
尹东
王平
郑先伟
CHENG Aiping;LI Xinpeng;YIN Dong;WANG Ping;ZHENG Xianwei(School of Resources and Environmental Engineering,Wuhan University of Science and Technology,Wuhan 430081,China;Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgical Mineral Resource,Wuhan 430081,China;Chengchao Mining Co.,Ltd.,Wuhan Iron and Steel Resources Group,Ezhou 436051,China)
出处
《金属矿山》
CAS
北大核心
2024年第9期34-41,共8页
Metal Mine
基金
国家自然科学基金项目(编号:51604195)
湖北省自然科学基金项目(编号:2018CFC818)
金属矿山高效开采与安全教育部重点实验室开放基金项目(编号:ustbmslab201704)。
关键词
胶结充填体
动态强度
入射能
破坏模式
RHT模型
cemented backfill
dynamic strength
incident energy
destruction mode
RHT model
