总结分析了在花岗岩中进行的1～150 kg TNT系列化爆试验的应力波测试数据,按岩性区分,给出了相应的自由场应力波衰减规律,其地运动参数的规律较强。与核爆结果对比表明,化爆试验的应力波衰减较快,其原因在于小药量化爆的应力波传播对岩...总结分析了在花岗岩中进行的1～150 kg TNT系列化爆试验的应力波测试数据,按岩性区分,给出了相应的自由场应力波衰减规律,其地运动参数的规律较强。与核爆结果对比表明,化爆试验的应力波衰减较快,其原因在于小药量化爆的应力波传播对岩体状况较敏感。基于化爆试验测试结果和现场岩性及工程施工状况,分析了应力测值偏低和分散的原因,讨论了现场应力波测试中所需注意和解决的问题,指出用粒子速度测值转换的应力比直接测量的应力更能反映现场岩体中的应力状况。展开更多
In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation pr...In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped lattices.The effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and analyzed.The target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent lattices.The proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k Hz.After the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target frequency.These results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.展开更多
文摘总结分析了在花岗岩中进行的1～150 kg TNT系列化爆试验的应力波测试数据,按岩性区分,给出了相应的自由场应力波衰减规律,其地运动参数的规律较强。与核爆结果对比表明,化爆试验的应力波衰减较快,其原因在于小药量化爆的应力波传播对岩体状况较敏感。基于化爆试验测试结果和现场岩性及工程施工状况,分析了应力测值偏低和分散的原因,讨论了现场应力波测试中所需注意和解决的问题,指出用粒子速度测值转换的应力比直接测量的应力更能反映现场岩体中的应力状况。
基金National Natural Science Foundation of China(Grant Nos.51821003,52175524,61704158)the Natural Science Foundation of Shanxi Province(Grant No.202103021224206)Shanxi"1331 Project"Key Subjects Construction to provide fund for conducting experiments。
文摘In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped lattices.The effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and analyzed.The target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent lattices.The proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k Hz.After the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target frequency.These results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.
