摘要
为了研究尺寸效应对材料力学性能的影响,利用MTS(材料试验系统)和SHPB(分离式霍普金森压杆)试验装置,对不同长径比石灰岩试件进行了准静态和动态冲击压缩试验。试验结果表明:准静态加载条件下,岩石试件的强度随长径比的增大而减小;而动态冲击条件下,试件长径比对强度的影响存在一个临界值。长径比低于临界值,强度随长径比的增大而减小;长径比高于临界值,强度随长径比的增大而增大。对于高于临界长径比的岩石试件,存在临界加载速度,低于临界加载速度,静态尺寸效应占主导地位;高于临界加载速度,动态尺寸效应占主导地位。
In order to research the size effect to material mechanics performances, the material test system （MTS） and SHPB （Split Hopkinson Pressure Bar） experiment device were applied to the parastatic and dynamic impact compressed test of the different length-radius ratio limestone specimens. The test results showed that under the parastatic loading conditions, the strength of the rock specimen will be reduced with the increasing of the length-radius ratio. Under the dynamic impact conditions, there would be a critical value of the length-radius ratio affected to the strength of the specimen. When the length-radius ratio less than the critical value, the strength of the specimen would be decreased with the increasing of the length-radius ratio. When the length-radius ratio higher than the critical value, the strength of the specimen would be increased with the increasing of the length-radius ratio. As for the rock specimens higher than the critical length- radius ratio, there would be a critical loading velocity which would be lower than the critical loading velocity and the static size effect would be in a main leading position. As higher than the critical loading velocity, the dynamic size effect would be in the leading position.
出处
《煤炭科学技术》
CAS
北大核心
2009年第4期19-22,68,共5页
Coal Science and Technology
基金
国家自然科学基金资助项目(50674049)
