三轴压缩下岩石的宏细观蠕变损伤演化研究  

Study on Macro-micro Creep Damage Evolution of Rock Under Triaxial Compression

作　　者：齐文超 魏振阁 陈小龙 刘硕 陶逢春 Qi Wenchao;Wei Zhenge;Chen Xiaolong;Liu Shuo;Tao Fengchun(CSCEC-TAISEI Construction,LTD.,Beijing 100070,China)

机构地区：[1]中建-大成建筑有限责任公司,北京100070

出　　处：《黑龙江科学》2023年第20期47-49,共3页Heilongjiang Science

摘　　要：从细观力学角度出发,研究三轴压缩条件下岩石蠕变特性,用反映岩石宏观蠕变损伤的基准量联系细观参量,建立岩石宏细观力学模型,求得微裂纹尖端的应力强度因子及宏细观蠕变关系式,对选取的砂岩进行算例分析与试验分析,探究微裂纹扩展规律及岩石的蠕变特性。结果表明,应力差与初始裂纹倾角对应力强度因子值有显著影响,当倾角φ增大到一定值时,应力强度因子K I出现负值,即微裂纹将不再发生纯I型裂纹破裂,理论曲线与试验曲线走势基本一致,可有效反映岩石的蠕变过程,研究结果为长期服役的基础岩体工程稳定性控制提供了一定的理论基础。From the perspective of micromechanics,the study analyzes the creep characteristics of rock under triaxial compression,combines with the mesoscopic parameters with the reference quantity reflecting the macroscopic creep damage of rock,establishes a macro-mesoscopic mechanical model of rock,obtains the stress intensity factor of the micro-crack tip and the macro-mesoscopic creep relation,selects sandstone by example and experiment,and explores the law of micro-crack propagation and the creep characteristics of rock.The results show that the stress difference and initial crack inclination have significant influence on the value of the stress intensity factor.When the inclinationφincreases to a certain value,the stress intensity factor K I will appear negative,i.e.the microcrack will no longer occur pure type I crack rupture.The trend of the theoretical curve is basically the same as that of the test curve,which can effectively reflect the creep process of the rock.Results of the research provide a certain theoretical basis for the stability control of foundation rock mass engineering in long-term service.

关 键 词：宏细观力学模型 裂纹扩展 应力强度因子 蠕变特性 

分 类 号：TU45[建筑科学—岩土工程]