泥岩变温蠕变试验温度修正及蠕变特性

以郓城煤矿泥岩为研究对象，进行了常温范围内泥岩变温三轴压缩蠕变试验，试验结果表明常温范围内温度对泥岩蠕变应变影响较大，对泥岩蠕变速率影响较小，进行泥岩蠕变特性分析前必须对蠕变试验结果进行温度修正。根据温度周期变化下岩石稳态蠕变试验结果，提出了常温范围内岩石蠕变试验温度修正方法，该方法能较好的辨识得到岩石的温度应变率以及岩石的稳态蠕变速率，采用该温度修正方法对泥岩变温蠕变试验结果进行了辨识和修正，结果表明常温范围内围压25 MPa条件下泥岩温度应变率约为2.80×10-5 /℃，修正后泥岩蠕变特性与西原模型相符，试样的稳态蠕变速率与轴向偏应力近似呈线性关系。

Creep property of mudstone under variable temperature and temperature correction

To study the mudstone buried in Yuncheng mine,a tri-axial compression creep test was undertaken,and the temperature in this experiment varied coincidently with the environment temperature.It was shown that the temperature has a great effect on the creep strain of mudstone,but has little effect on the creep rate,which indicates that the experiment result must be modified before it is analyzed.By analyzing the test result of mudstone in steady creep stage under cyclic temperatures,a new way to do the temperature corrections in a creep test was proposed,which can identify the thermal-strain rate and creep rate separately.The creep test result of mudstone under cyclic temperatures was adopted to verify and the thermal-strain rate of mudstone was calculated to be 2.80×10-5/℃ under a 25 MPa confining stress in room temperature range,and the modified creep test result of mudstone matched well with the Nishihara model.There is an obviously linear relationship between the steady creep rate and the axial deviatoric stress.