大理岩三轴压缩变形破坏与能量特征研究

利用伺服试验机对大理岩进行了常规三轴压缩试验,基于试验结果,研究了岩样三轴压缩变形破坏及其能量特征。结果表明,低围压时岩样内部材料并未均匀化,岩石表现为应变软化特性;而高围压时岩样内部材料强度由低到高逐渐屈服,变形趋于均匀,岩石出现塑性流动特性。岩石峰值应变与围压成正线性关系;岩石残余强度对围压的敏感性显著高于峰值强度。岩石破坏应变能随着围压的增大而增大,且两者成正线性关系;岩石全部断裂能随着围压的增加亦成正线性增加。

STUDY ON THE DEFORMATION FAILURE AND ENERGY PROPERTIES OF MARBLE SPECIMEN UNDER TRIAXIAL COMPRESSION

In the paper,experiments were carried out to investigate marble specimens under conventional triaxial compression by the RMT-150B servo-controlling testing machine.Based on the experimental results,the deformation failure and energy properties of marble specimens under conventional triaxial compression were studied.The results show that marble will manifest the property of strain inteneration when the material in the rock does not turn uniform under the lower confining pressure.However,marble will show the property of plastic flowage when the material deformation becomes uniform under higher confining pressure.There is a a positive linear relation between the peak strain of rock material and the confining pressure.The sensitivity of residual strength on the confining pressure is higher than that of peak strength.The failure strain energy of rock increases linearly as the confining pressure increases.The total fracture energy of rock specimens also increases linearly as confining pressure increases.