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近年来,利用断层产物以及其中的颗粒来研究断层或地震带的能量耗散与释放,已引起大家的重视.在围压分别为30kPa、60kPa、100kPa、200kPa、400kPa和600kPa的条件下,采用直径为0.6~0.8mm的玻璃珠以0.02mm/min的轴向应变速率进行干燥、松散细颗粒材料的固结不排水三轴压缩试验.为了减少轴向应变过大时主应力轴旋转产生的误差及其对做功的影响,试验只分析加载后轴向应变为10%时试样变形破坏过程中的能量耗散与能量释放特性.试验结果表明:随着围压的增大,主震频率减小、偏应力降幅增大,但偏应力降幅与最大偏应力的比值逐渐趋于稳定.粘滑运动过程中,在偏应力骤降瞬间,声发射强烈、试样体积收缩,说明能量控制着试样的变形与破坏特征,耗散结构能量越大,系统发生滑动的频率越小.粘滑运动过程可以表示为能量耗散与能量突然释放.最后,从热力学的角度分析滑动过程的3个阶段,得出粘滑运动为不可逆耗散能与可释放应变能共同作用的结果.
In recent years, the use of fault products and the particles therein to study the energy dissipation and release of faults or seismic belts has drawn people’s attention.Under the confining pressures of 30kPa, 60kPa, 100kPa, 200kPa, 400kPa and 600kPa respectively, Glass beads with a diameter of 0.6-0.8 mm were dried at an axial strain rate of 0.02 mm / min, and consolidated loose undrained triaxial compression tests of loose fine particulate materials were carried out.In order to reduce the rotation of the principal stress axis when the axial strain is too large Error and its effect on the work, the test only analyzes the energy dissipation and energy release characteristics of the specimen during the deformation and failure of the specimen after the axial strain is 10% .Experimental results show that as the confining pressure increases, And the ratio of the deviatoric stress drop to the maximum deviatoric stress tends to be stable gradually.When the stick-slip movement occurs, the acoustic emission is strong and the sample volume shrinks at the moment when the deviatoric stress suddenly drops, indicating that the energy control The deformation and failure characteristics of the sample, the larger the energy of the dissipative structure, the smaller the frequency of the system slip occurs.The stick-slip motion process can be expressed as the energy dissipation and the sudden release of energy.Finally, from the thermodynamic point of view, Cheng three stages, obtained stick-slip can result irreversible dissipate strain energy interacts with the releasable.