冻融作用下岩石的微观损伤及动态力学特性（英文）

发布时间：2018-06-20 15:45

本文选题：岩石 + 冻融循环　；参考：《Transactions of Nonferrous Metals Society of China》2015年04期

【摘要】：为研究冻融循环作用下岩石的微观损伤及动态力学特性,对5组均质砂岩进行不同冻融循环次数的冻融试验,并对冻融后的砂岩进行核磁共振测试以及冲击荷载试验,获得冻融作用下砂岩的微观损伤特征及动态力学参数。结果表明:孔隙度随冻融循环次数的增加而增大,冻融初期的孔隙度增长率趋缓,在达到一定冻融循环次数后孔隙扩展加快;不同尺寸的孔隙比例随冻融循环次数呈动态变化,且孔隙结构总体趋向多尺寸分布发展;冻融砂岩的动态压缩应力-应变曲线可以分为4个阶段,相比静态曲线其压密阶段不明显;随着冻融次数的增加,砂岩的弹性模量和动态峰值强度逐渐减小,而峰值应变则有所增大;砂岩孔隙度越大,动态峰值强度越小,且拟合曲线呈多项式分布。
[Abstract]:In order to study the microcosmic damage and dynamic mechanical properties of rock under freeze-thaw cycle, five groups of homogeneous sandstone were tested with different freezing and thawing cycles, and the frozen and thawed sandstone were tested by NMR and impact load. The microscopic damage characteristics and dynamic mechanical parameters of sandstone under freezing and thawing are obtained. The results show that the porosity increases with the increase of freeze-thaw cycles, the porosity growth rate slows down at the beginning of freezing and thawing, and the pore expansion accelerates after a certain number of freeze-thaw cycles, and the pore ratio of different sizes varies dynamically with the number of freeze-thaw cycles. The dynamic compression stress-strain curve of freeze-thawed sandstone can be divided into four stages, but its compaction stage is not obvious compared with static curve, and with the increase of freeze-thaw times, The elastic modulus and dynamic peak strength of sandstone gradually decrease, while the peak strain increases, and the larger the porosity of sandstone, the smaller the dynamic peak strength, and the polynomial distribution of fitting curve.
【作者单位】：中南大学资源与安全工程学院;中南大学高海拔寒区采矿工程技术研究中心;
【基金】：Project(2013YQ17046310)supported by the National Key Scientific Instrument and Equipment Development Project of China Project(2013M542138)supported by China Postdoctoral Science Foundation Projects(20130162110010,20130162120012)supported by Specialized Research Fund for the Doctoral Program of Higher Education of China
【分类号】：TU45

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