考虑孔隙度及泥质含量影响的中砂岩分数阶蠕变模型

发布时间：2018-05-02 19:02

本文选题：砂岩 + 分级蠕变　；参考：《金属矿山》2017年12期

【摘要】：为探究砂岩蠕变力学行为受自身含泥量及孔隙度的影响,分别对取自某矿井的4组不同含泥量和孔隙度砂岩进行了分级加载蠕变试验。试验结果表明:泥质含量越高、孔隙度越小,砂岩的强度越低;稳态蠕变速率随应力的增长呈幂函数增加;在相同加载应力比下,泥质含量越高、孔隙度越小的砂岩稳态蠕变速率越高,蠕变破坏应力比越低,变形量越大,长期强度特征值越小;应力敏感性常数与泥质含量及孔隙度之比呈良好的幂函数型关系;基于分数阶蠕变本构模型,建立了一种新的考虑泥质含量、孔隙度以及应力水平、受力时间影响的砂岩分数阶蠕变本构模型,通过参数敏感性分析及试验结果反演推算,验证了该模型能较好地模拟各含泥量和孔隙度下在不同应力状态下的蠕变状态。
[Abstract]:In order to investigate the influence of sandstone creep mechanical behavior on its own mud content and porosity, four groups of sandstone with different shale content and porosity from a mine were tested by graded loading creep tests. The experimental results show that the higher the content of clay, the smaller the porosity, the lower the strength of sandstone, the higher the steady state creep rate increases with the increase of stress, and the higher the content of clay is under the same loading stress ratio. The smaller the porosity is, the higher the steady creep rate of sandstone is, the lower the creep failure stress ratio, the larger the deformation, the smaller the long-term strength characteristic value, the better the power function relationship between stress sensitivity constant and the ratio of shale content and porosity. Based on the fractional creep constitutive model, a new fractal creep constitutive model of sandstone considering the influence of shale content, porosity, stress level and stress time was established. It is verified that the model can well simulate the creep state under different stress states with different mud content and porosity.
【作者单位】：常州工程职业技术学院建筑工程学院;
【基金】：江苏省科技计划前瞻性联合研究项目(编号:BY2014108-26) 住房和城乡建设部科技计划项目(编号:2014-K3-034,2016-R1-012)
【分类号】：TD315

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