煤岩单轴加载统计损伤本构模型
Uniaxial Loading Statistical Damage Constitutive Model for Coal and Rock
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摘要: 为了研究煤岩单轴加载过程中的损伤演化规律，对煤岩进行了单轴加载实验，得到了煤岩的应力应变曲线、环向-轴向应变曲线。实验结果表明，煤岩加载过程中环向应变速率随着轴向应变的增加呈现出非线性增加的规律，并在煤岩加载进入软化阶段后达到最大值，它在宏观上反映了煤岩内部裂纹的产生与发展，并与煤岩的损伤演化规律相符。故定义损伤变量为裂纹体积的函数，并假设裂纹体积的增加符合威布尔统计规律，构建了煤岩统计损伤本构模型，通过与实验结果对比，验证了该模型的正确性。Abstract: In order to study the laws of damage evolution of coal and rock under uniaxial loading, the uniaxial loading test of coal and rock was done, and we obtained the stress strain curve and hoop to axial strain curve of coal and rock. The experimental results show that the hoop strain rate increases with the increase of axial strain, which presents nonlinear law in the loading process of coal and rock, and the increase rate reaches the maximum value when the coal is loaded into softening stage, which reflects the generation and development of internal crack of coal and rock at macro level, and conforms with the damage evolution law of the coal. So defining the damage variable as a function of crack volume, assuming the increase volume of crack conforms to Weibull statistical law, constructing a statistical damage constitutive model of coal, comparing with the experimental results, it verifies the correctness of the model.
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Keywords:
- hoop strain /
- damage mechanics /
- constitutive equation /
- statistical distribution /
- rock mechanics
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[1] 王思敬.论岩石的地质本质性及其岩石力学演绎[J].岩石力学与工程学报,2009（3）:433-450. [2] 谢和平.岩石、混凝土损伤力学[M].徐州:中国矿业大学出版社，1990. [3] 任建喜,葛修润.单轴压缩岩石损伤演化细观机理及其本构模型研究[J].岩石力学与工程学报,2001（4）:425-431. [4] 李术才,许新骥,刘征宇，等. 单轴压缩条件下砂岩破坏全过程电阻率与声发射响应特征及损伤演化[J].岩石力学与工程学报,2014（1）:14-23. [5] 杨永杰,王德超,郭明福,等.基于三轴压缩声发射试验的岩石损伤特征研究[J].岩石力学与工程学报,2014（1）: 98-104. [6] 郭子红,刘新荣,刘保县，等.基于塑性体积应变的岩石损伤变形特性实验研究[J].实验力学,2010（3）:293-298. [7] Lemaitre J.How to use damage mechanics[J].Nuclear Engineering and Design,1984,80：233-245. [8] 徐松林,吴文，李廷，等.三轴压缩大理岩局部化变形的试验研究及其分岔行为[J].岩土工程学报,2001（3）:296-301. [9] 王丽. 巷道围岩流变损伤及应力演变理论研究与数值模拟[D].北京：中国矿业大学(北京),2012. [10] 秦跃平. 煤岩损伤与动力灾害的理论与试验研究[D].北京：中国矿业大学（北京），2003.
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