Development of multi-field rock resistivity test system for THMC
Development of multi-field rock resistivity test system for THMC
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DOI：
10.5194/se-14-261-2023
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发表时间：
2023-03
期刊：
影响因子：
3.4
通讯作者：
J. Ren;Lei Song;Qirui Wang;Haipeng Li;Junqi Fan;J. Yue;Honglei Shen
中科院分区：
文献类型：
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作者：
J. Ren;Lei Song;Qirui Wang;Haipeng Li;Junqi Fan;J. Yue;Honglei Shen
抽象。为研究深部地下环境条件下岩石力学性质与电阻率的关系，研制了一套可实现温度、压力、渗流和化学环境同时控制的岩石电阻率测试系统，并探索了相应的封孔方法。该系统主要包括三轴系统、化学渗透系统、温度控制系统和测试控制系统。通过测试和初步实验验证了系统的可靠性。利用该试验系统对花岗岩裂隙试件在渗流-温度耦合作用下的电阻率以及未冻煤和冻融煤在三轴压缩过程中的电阻率进行了测试。试验结果表明，裂隙花岗岩在低渗透压力下，温度引起的电阻率变化较大，温度越低，渗透对岩石电阻率的影响越大。未冻煤和冻融煤在三轴压缩过程中的电阻率变化规律差异较大。未冻煤样的电阻率在初始压缩阶段呈现出减小的趋势，然后随着偏应力的增大而逐渐增大。冻融后煤的电阻率在整个压缩过程中呈下降趋势。
Abstract. To study the relationship between rock mechanical properties and resistivity under deep-underground environmental conditions, a rock resistivity test system, which can realize the simultaneous control of temperature, pressure, seepage, and the chemical environment, was developed; further, a corresponding specimen-sealing method was explored. The system primarily comprises a triaxial system, chemical permeation system, temperature control system, and test control system. The reliability of the system was verified through tests and preliminary experiments. The resistivity of fractured granite specimens under coupling of seepage and temperature and the resistivity of unfrozen and freeze–thawed coals during triaxial compression were tested with this test system. The test results show that the temperature-induced resistivity change is greater at low seepage pressures for fractured granites, and the effect of seepage on rock resistivity is greater at lower temperatures. The resistivity change patterns of unfrozen and freeze–thawed coals during triaxial compression differ quite significantly. The resistivity of unfrozen coal specimens exhibits a decreasing trend in the initial compression stage and then gradually increases with rises in the deviatoric stress. After freezing and thawing, the electrical resistivity of coal decreases during the entire compression process.