【作者】 贺玉龙；

【导师】 杨立中；

【作者基本信息】 西南交通大学 ， 岩土工程， 2003， 博士

【摘要】 温度场、渗流场和变形场是岩体物理地质力学环境的重要组成部分，这三个场之间存在高度非线性的复杂耦合作用，即THM耦合作用。近20年来，三场耦合理论取得了很大的进展，但作为一个新兴的交叉研究领域，三场耦合理论的研究还存在不少问题。本文结合国家自然科学基金项目，对当前三场耦合研究领域中存在的一些问题进行了研究。 论文进行的主要工作及取得的主要结论以及创新性成果包括： (1)从三场耦合作用模式、三场耦合数学模型和相关试验研究3个方面比较全面地总结了三场耦合的国内外研究现状。 (2)根据连续性方程、线动量平衡方程和能量守恒方程以及相应的物性方程推导了饱和岩体温度场-渗流场-变形场三场耦合作用控制方程组。在推导控制方程组时舍弃了“局部热平衡”假设，采用了热弹塑性本构关系，考虑了温度梯度对地下水渗流的影响(类Soret效应)以及地下水的粘性耗散对岩体温度场的影响。 (3)在不同温度水平和不同有效应力水平下，进行了砂岩的孔隙度试验。试验结果表明，有效应力对砂岩孔隙度的影响较大，在温度一定的情况下，砂岩的孔隙度随有效应力的增加而呈负指数规律减小；而温度变化(本试验中的温度变化范围为37.6℃)对砂岩孔隙度的影响很小。 (4)在不同温度水平和不同有效应力水平下，进行了砂岩的渗透率试验。试验结果表明，温度的升高或(和)有效应力的增加都将导致砂岩渗透率的减小。在温度一定的条件下，砂岩的渗透率和水力传导系数均随有效应力的增加而呈负指数规律减小，但在有效应力一定的条件下，水力传导系数与温度之间的关系函数并非单调函数。 (5)根据对试验结果的分析，初步提出了温度和有效应力对渗透率的影响机理。就本试验所用砂岩而言，有效应力对渗透率的影响主要在于有效应力对孔隙，尤其是对喉道的压缩作用；而温度对渗透率的影响则主要在于随温度升高而加剧的粘土矿物的分散作用以及砂岩骨架的热膨胀对喉道的压缩作用。 (6)进行了围压升降过程中砂岩岩样和单裂隙试件的渗透率试验。试验结果表明，在围压升降过程中，砂岩和单裂隙花岗岩的渗透率均随有效应西南交通大学博士研究生学位论文第日页力的增加呈负指数规律减小，但单裂隙试件的渗透率对有效应力的敏感程度远大于砂岩，而砂岩渗透率的恢复程度则远大于单裂隙试件。在围压下降过程中，砂岩和单裂隙试件渗透率的恢复均存在明显的应力滞后效应。 (7)根据多方收集到的资料，考察了温度和压力对岩石和地下水物性参数的影响。研究表明，与压力的影响相比，温度对岩石和地下水物性参数的影响更大。本文给出了地下水物性参数与温度之间精度较高的关系式。 (8)在前人研究的基础上，根据试验研究给出了比较全面的三场祸合作用模式;根据祸合作用实现方式的不同，将三场藕合机理分为两类:“力学”祸合和“参数”祸合。 (9)进行了温度场、渗流场和变形场三场两两祸合作用强度的量化研究，发展并完善了6个祸合强度量化参数，为三场祸合数学模型的合理简化提供了一种依据，对推进三场祸合理论的工程应用具有一定的现实意义。更多还原

【Abstract】 As the important components of physical geologic environment for rock mass, temperature field, seepage field and stress or strain field are coupled, namely coupled Thermal-hydro-mechanical(THM) behaviour, which is highly non-linear and complex. Over the past twenty years, great advances have been made in the area of THM coupling theory. However, as a rising interdisciplinary subject, there are several shortages in this area. Funded by NSF,this thesis develops the research on several shortages in the area of THM coupling theory.The main efforts, conclusions and innovative results gained can be expressed as follows.(1) From research achievements obtained on coupling mechanisms, mathematical model and test studies, state-of-the-art of studies on thermo-hydro-mechanical coupling in rock and soil mass are systematically reviewed.(2) On the basis of continuity equation, momentum conservation equation, energy conservation equation, and substantial equation, coupled THM governing equations are derivated with giving up the assumption of local thermal equilibrium, adopting thermal elasto-plastic constitutive relation, taking the effect of temperature gradient on groundwater seepage(analogous to Soret diffusion) and the effect of viscous dissipation of groundwater on temperature field of rock mass into account.(3) The porosity test for sandstone was conducted at various temperature level and various effective stress level. The testing results show that the porosity of sandstone decreases with increasing effective stress at the fixed temperature level, following the law of negative exponent. However, at the fixed effective stress level, the effect of temperature on the porosity of sandstone is very small (37.6℃ temperature variation).(4) The permeability test for sandstone was conducted at various temperature level and various effective stress level. The testing results show that the permeability of sandstone decreases with rising temperature and/or increasing effective stress. At the fixed temperature level, both the permeability and hydraulic conductivity of sandstone decrease with theincreasing effective stress, following the law of negative exponent. At the fixed effective stress level, however, the function between hydraulic conductivity and temperature is not a monotone one.(5) According to the analysis on tests results, the effect mechanism of temperature and effective stress on the permeability is put forward. As far as the sandstone adopted, the effect of effective stress on permeability lies in pressure effect of effective stress on pore and throat, and that of temperature lies in aggravating disaggregation of clay mineral with rising temperature and pressure effect of skeleton expansion on throat.(6) The permeability tests for sandstone and granite with a single fracture were conducted in the process of loading-unloading for confining pressure. The test results show that both the permeability of sandstone and that of granite with a single fracture decrease with increasing effective stress, following the law of exponential decay. The permeability sensitivity of granite to effective stress is more stronger than that of sandstone, but the permeability recovery capability of sandstone is more stronger than that of granite. Moreover, for sandstone and granite with a single fracture, there is obvious hysteresis effect for the restitution of permeability in the process of unloading for confining pressure.(7) Based on the collected data, the effect of temperature and pressure on physical properties of rock and groundwater is researched. The effect of temperature is more greater than that of pressure. The high-precision formula between physical properties of groundwater and temperature are presented.(8) On the basis of previous studies, improved pattern of THM coupling is put forward. Ground on different coupling mode, THM coupling mechanism are classified two sorts as mecha更多还原