【作者】 崔少东；

【导师】 刘保国；

【作者基本信息】 北京交通大学 ， 岩土工程， 2010， 博士

【摘要】 本文在已有研究成果的基础上,研制开发了一套新型的流变仪器,以泥岩为研究对象,对该岩石的瞬时强度特性、单轴和三轴流变特性进行了系统、全面的研究,得到了泥岩的基本力学参数包括弹性模量E、内聚力C、内摩擦角(?)随应力和时间的弱化规律,并将其引入Bingham一维流变模型和P.Perzyna三维流变模型中,建立了非定常的流变模型,最后成功的在ABAQUS软件中对其实现了二次开发,并通过试验数据验证了模型的正确性。本文完成的主要工作有：1.在分析现行流变仪器的优缺点的基础上,研制开发了一台新型的流变仪器—五联单轴流变仪,该仪器主要用于岩石的流变试验,能同时控制五个不同条件下的流变试验,实现了计算机自动控制、自动采集数据。2.进行了泥岩在OMPa、5MPa、10MPa和15MPa四个围压级别下的瞬时强度试验,得到了泥岩的变形和破坏规律,探讨了由瞬时强度试验确定岩石长期强度的方法。论述了单试件法测岩石力学参数的原理,并对其数据处理方法进行了修正。3.分析了岩石的蠕变损伤阀值,从细观力学和宏观力学两方面解释了岩石的蠕变过程曲线。进行了泥岩八个应力水平的单轴压缩蠕变试验,分析了其蠕变特性,采用单试件法对其蠕变过程中的三个时间点的力学参数进行了测定,得到了该泥岩力学参数随应力和时间的弱化规律。4.进行了5MPa、10MPa和15MPa三个不同围压下的蠕变试验,将单轴条件下泥岩力学的弱化规律扩展到了三轴状态,通过蠕变破坏时的强度进行了验证。5.将泥岩的力学参数弱化规律引入到了Bingham模型中,建立了泥岩的一维非定常流变模型,并通过试验数据验证了模型的合理性。采用Drucker-Prager准则将一维的Bingham模型扩展到了三维的P.Perzyna模型,通过引入非定常的力学参数建立了三维的非定常流变模型。6.在ABAQUS软件中对三维的P.Perzyna模型实现了二次开发,通过试验数据验证了模型的正确性。更多还原

【Abstract】 ABSTRACT:Based on the researches achieved, a novel man-made rheological instruments was developed in this thesis, in which mudstone was used as subject investigated. The instantaneous strength property, uniaxial and triaxial rheological characteristics of rock was investigated systematically and comprehensively, and the weakening regularity was explored which the basic mechanical parameters, the deformation modulus (E), cohesion (C) and internal friction angle(φ), all degraded gradually with time and stress in the process of rock creep. Moreover, an unsteady rheological constitutive model was presented through introducing this weakening regularity into Bingham one-dimensional rheological model and P.Perzyna three-dimensional rheological model. At last, the secondary development of unsteady rheological constitutive model using ABAQUS software was realized successfully, and this model was verified to be correct by experimental data. The main works completed in this thesis were as followed:1. A novel man-made rheological instruments, namely five-Joint uniaxial rheological apparatus, was developed which can be used for rock rheological tests on the basis of analysis of merits and drawbacks of current rheological instrument. The five rheological experiments at deferent conditions could be carried simultaneously by using this new instrument, and automatic control and automatic data collection in the experiment could be implemented by computer.2. The instantaneous strength experiments of mudstone under four confining pressure condition:OMPa,5MPa, 10MPa and 15MPa were carried out, and the deformation and failure laws of mudstone were obtained. Thus, a new method was presented that long strength of rock could be determined by instantaneous strength test of rock. In addition, measuring principle of rock mechanics parameters using single specimen method was discussed and its data processing method was modified.3. Based on the analysis of creep damage threshold of rock, the creep process curves was explained through micro and macro mechanics. The uniaxial creep test of mudstone at eight stress levels was carried out, and then its creep characteristics were analyzed. The three time-point mechanics parameters were measured in the process of creep by single specimen method, thus the weakening regularity was obtained which the basic mechanical parameters all degraded gradually with time and stress.4. The creep deformation experiments were carried out at three different confining pressures of 5MPa, 10MPa and 15MPa. Thus, the weakening regularity of mudstone mechanical parameters of uniaxial conditions could be extended to triaxial condition, and was verified through creep destroyed strength of rock.5. Introducing weakening regularity of mudstone mechanical parameters into Bingham model, one-dimensional unsteady rheological model was established, and rationality of this model was verified by experimental data. Furthermore, one-dimensional Bingham model was extended to three-dimensional P.Perzyna model through using Drucker-Prager criterion, so the three-dimensional unsteady rheological model was established through introducing unsteady mechanical parameters.6. The secondary development of the three-dimensional P.Perzyna model using ABAQUS software was realized, and the rationality of this model was examined through experimental data.更多还原