考虑非贯通节理损伤演化岩体复合本构模型

发布时间：2018-05-15 00:06

本文选题：非贯通闭合节理 + 损伤　；参考：《哈尔滨工业大学学报》2017年06期

【摘要】：非贯通节理岩体的力学特征与完整岩石相比有较大差异.为推导非贯通节理岩体在单轴压缩下的复合损伤本构模型,采用修正自洽方法考虑不同损伤变量之间的复合.从附加应变能增量和损伤应变能释放量相关联的思路出发,采用等效直线裂纹作为节理裂隙损伤演化轨迹,分别计算细观损伤、初始节理和节理裂隙损伤演化引起的附加应变能;基于Betti能量互易定理,引入自洽方法考虑节理裂隙之间的相互作用,并采用逐条添加节理的方法对传统自洽方法进行修正,得出岩体不同受力阶段细观、初始节理和节理裂隙损伤演化的复合损伤本构模型;将本构模型的理论计算结果与现有文献的室内试验结果进行对比分析,结果显示:本构模型的理论计算结果与室内试验结果规律一致,随着节理个数增加,初始弹性模量和荷载峰值均呈下降趋势,下降幅度较为一致;节理裂隙的损伤演化对岩体的力学特性有重要影响,考虑节理裂隙损伤演化的理论应力应变曲线和荷载峰值与室内试验结果更为吻合,有效验证了复合损伤本构模型的正确性与合理性.
[Abstract]:The mechanical characteristics of non-jointed rock mass are quite different from those of intact rock mass. In order to deduce the composite damage constitutive model of non-transfixion jointed rock mass under uniaxial compression, the modified self-consistent method is used to consider the composite of different damage variables. Based on the thought of the correlation between the increment of additional strain energy and the amount of damage strain energy, the equivalent linear crack is used as the damage evolution track of joint fracture, and the mesoscopic damage is calculated respectively. Based on the Betti's energy reciprocity theorem, the self-consistent method is introduced to consider the interaction between joints, and the traditional self-consistent method is modified by adding joints one by one. The composite damage constitutive model for the damage evolution of the initial joints and joints in different stress stages of rock mass is obtained, and the theoretical calculation results of the constitutive model are compared with the results of laboratory tests in the existing literature. The results show that the theoretical results of the constitutive model are consistent with the experimental results. With the increase of the number of joints, the initial modulus of elasticity and the peak value of load are decreasing, and the decreasing range is consistent. The damage evolution of joints has an important effect on the mechanical properties of rock mass. The theoretical stress-strain curve and load peak value considering the damage evolution of jointed fractures are in good agreement with the results of laboratory tests. The validity and rationality of the composite damage constitutive model are verified effectively.
【作者单位】：四川大学水利水电学院;水力学与山区河流开发保护国家重点实验室(四川大学);四川省交通运输厅公路规划勘察设计研究院;
【基金】：国家重点基础研究发展计划(2015CB057903)
【分类号】：TU452

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