摘要
为了解花岗岩的动态力学性能,采用φ50mm Hopkinson压杆对岩石进行动态冲击压缩试验,应变率范围为25.4～193.4s-1,采用波形整形技术获得平滑的脉冲荷载,得出岩石的动态应力–应变曲线。试验结果表明:岩石抗压强度具有明显的应变率效应,破坏强度随着应变率的增加而增大,相对于静态强度120MPa,最高动态强度增大至365MPa,约为静态强度的3倍;冲击荷载较低时,试样内部出现损伤及微小裂纹,荷载强度增大时,试样出现宏观裂纹及破碎成块,当荷载进一步增大时,试样呈粉碎性破坏。研究结果可为国防工程结构设计提供参考。
To understand the dynamic mechanical properties of rocks,a series of dynamic shock compression tests were carried out by using φ 50 mm Hopkinson pressure bar apparatus,with strain rate range from 25.4 to 193.4 s-1. Wave shaping technique was used to smooth pulse load;dynamic stress-strain curves were obtained. Experiment data show that the strength of rock has an obvious strain rate effect. The value of strength increases with increasing strain rate. Compared with static strength of 120 MPa,the maximum dynamic strength is enhanced to 365 MPa at strain rate of 193.4 s-1. With the increase in dynamic load,specimen experiences a process of the generation of internal damage,micro flaw,macro crack,fracturing to nubbins and crushing to pieces. The results are valuable for military structure design.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2010年第A02期4153-4158,共6页
Chinese Journal of Rock Mechanics and Engineering
