【作者】 王颖；

【导师】 李小春；

【作者基本信息】 中国科学院研究生院（武汉岩土力学研究所） ， 岩土工程， 2009， 博士

【摘要】 渗透性是多孔介质材料的一种非常重要的性质，常用渗透系数来表示。天然岩石（多孔介质）的渗透系数分布范围超过10个数量级，此外，这些多孔介质材料（包括各种地质和工程材料）在复杂地质作用和／或人为作用（如力学、温度、化学、生物等）下，其渗透性能会发生大幅度变化，渗透系数变化达数个量级。现有的室内渗透系数测量方法并不能完全满足上述测量需求，迫切需要一种能够适应多时间尺度（即测量快速）和大量程变化且高效稳定的渗透系数测量方法，为流体矿藏的开采和废弃物的埋储等重大工程项目中关于储层及地层的渗透性及其变化规律的评价提供有效的手段和方法。本文总结前人的研究成果，基于瞬态压力脉冲法的特点及优势，针对该方法在测量量程上的局限，提出变容压力脉冲渗透系数测量新思路，并成功研发了变容测量装置。本文利用岩石水力学、渗流力学、有限元数值模拟以及室内试验对变容压力脉冲渗透系数测量方法进行了系统的研究，内容包括理论建立、系统设计、装置制作、实验验证、误差分析、应用延伸。室内渗透实验对多孔介质材料渗透系数测量结果的影响与被测试件本身的性质、实验系统的设计、装置的构造与性能等有关。所以同一块地质材料采用不同的渗透实验方法或测量装置所测得的渗透系数值是不一样的，同一块地质材料采用同种渗透实验方法及测量装置在不同的时期所测得的渗透系数值也是不一样的。因为没有已知渗透系数的标准试件，测量结果的精度难以明确说明，渗透实验方法及装置的精度和量程难以准确标定。如果渗透系数测量数据不准确，将会导致一些工程现象难以解释，甚至显得室内渗透实验毫无意义。迫切需要建立一套标定渗透实验的统一标准。本文利用粉末冶金学、流体力学、多孔介质力学以及室内试验对多孔介质标准试件进行了系统的研究，内容包括基于标定渗透实验的标准试件概念的建立、李氏标准件的设计、制备、保存、维护及使用、渗透实验的标定方法。本文研究的核心内容如下：第一，总结了各种室内渗透系数测量方法的原理及应用，分析了各种室内渗透实验方法的优缺点。为适应多时间尺度及大量程变化且高效稳定的渗透系数测量需求，利用瞬态压力脉冲法的非稳态流特点和测量快速的优势，提出一种快速、大量程且高精度的渗透系数测量新思路。（第二章和第四章）第二，分析了瞬态压力脉冲法的理论发展及参数分析，总结了该方法采用近似解法求解渗透系数的实验设计要点及注意事项，提出变容压力脉冲法的实验系统设计及装置结构设计方案。（第三章和第四章）第三，基于瞬态压力脉冲法的理论，针对该方法在测量量程上的局限，结合实验设计要点和测量经验，成功研发了变容脉冲渗透系数测量方法及测量装置，经理论和实践证明，该方法测量速度快（测量时间＜2.5h）、测量范围广(10^-7～10^-1D，跨越6个数量级)、测量精度高（偏差＜5％），满足多时间尺度和大量程变化且高效稳定的测量需求。（第四章）第四，基于变容压力脉冲法的理论进行思路扩展，提出了超低渗透测量方法及装置设计思路。理论表明，该超低渗透测量方法可以测量渗透性低至10^-10D的材料，如岩盐、泥岩等地质材料，同时还可以满足高孔隙压（20MPa以上）条件下的测量要求，适应多种荷载作用下的渗透测量，以模拟现场复杂地质作用下的岩石材料的渗透性变化，准确把握这些超低渗透性的地质工程材料的渗透性及其变化规律。（第四章）第五，总结了变容压力脉冲法渗透实验的13种误差源，归结为6种误差因素，采用有限元数值模拟方法，分析了变容脉冲法渗透实验过程中的6种误差因素对测量结果的误差影响程度，为优化实验操作、改进测量装置、进行误差标定提供有效参考。（第四章）第六，分析了岩石试件本身的性质、实验系统的设计、装置的结构和性能对被测岩石试件渗透系数测量精度的影响，说明单纯依靠渗透实验所测得的结果，其精度难以明确说明。提出了基于标定渗透实验的概念，提出了基于标定渗透实验的标准试件的概念和设计思路，弥补渗透测量技术领域关于精度和量程有效标定的空白。（第五章）第七，采用粉末烧结的方法，将粉末冶金学应用于多孔介质试件的制备。利用多孔介质材料各个物理性质参数之间的关系，成功设计并制备了李氏标准件，经长期渗透实验检测以及各种渗透条件下检测，表明该标准件的渗透系数稳定不变，以它们的渗透系数作为参照基准，为渗透测量领域提供有信服力的校核平台。（第五章）第八，利用李氏标准件，提出了渗透实验的标定方法，建立渗透测量技术的统一标准，渗透测量领域的校核平台。（第五章）更多还原

【Abstract】 With the growing concerns for resources and environmental issues in our society, the exploitation of fluid resources including petroleum, natural gas, coal bed methane, ground water atc, also the disposal of hazardous wastes including radioactive wastes, greenhouse gases etc, have become problems which are of considerable importance recently and will become increasingly significant in future years. Fluids and dissolved materials permeate through crustal rocks by processes of seepage and diffusion. However, the permeability of the geomaterials is, in many cases, the controlling factor in the above engineered exploitation and subsurface migration of hazardous wastes. The major problem encountered in the safety evaluation and construction design of the above engineering, however, is that the permeability of engineered materials distribute in a large range, probably well over 10 orders of magnitude and vary significantly so far as to several orders of magnitude, due to the changes in various kinds of environmental conditions and man-made disturbances including hydro-mechanical, temperature, chemical, biological reactions etc. However, the existing laboratory permeability measurement methods cannot meet the needs of measuring the coefficients of permeability of the above porous media materials completely. According to be capable of flexibility in testing situations of large-range-changing and changing quickly, a new kind of permeability measurement method, which is rapid, large range, high efficient and steady-going, will be required. It will provide an effective means to measure the permeability of reservoir or stratum or caprock materials, which are much accounted of fluid mineral storages exploitation and wastes underground storage stratum evaluation. In this dissertation, previous research results have been summarized, then, storage-variable transient pulse permeability measurement method has been proposed, which is a new kind of flexible testing technique. The new advanced testing method is based on traditional transient pulse method, but no limitations of narrow measuring range. Furthermore, the storage-variable transient pulse permeability testing device has been developed successfully. The storage-variable transient pulse permeability measurement method has been worked over systematically, involving theory deduction, system design, device manufacture, laboratory tests, error analysis and stretch of application. Meanwhile, referred to many research fields, the research work has been combined with rock hydraulics, permeation mechanics, FEM numerical simulation and laboratory tests.The errors of permeability testing results for porous media materials in laboratory experiment are related to qualities of specimen itself, the design of testing system, the constitution and performance of testing device and so on. Therefor, the testing results for the same specimen are different by using different permeability measurement methods or devices. Moreover, the testing results for the same sample are still different even by the same permeability measurement method and device if during different periods or under different conditions. Presently, there is no standard sample, the permeability of which is known, and can be able to be regarded as reference. So that, the accuracy of permeability testing results is difficult to describe definitely. Some engineering geological phenomena will also be difficult to explain, even the laboratory experiment seems making no sense, if the testing results are inaccuracy. It will be demanded urgently to establish a series of unified standards for calibrating permeation experiments. In this dissertation, the right demanded standard samples of porous media have been developed. Many more development researches have been made on the standard samples, including the proposal of the idea of standard sample for calibrating permeation experiments; the design of Li’s samples and their preparation, preservation, maintenance, transportation and application; the calibration method for permeation experiments. In the same meantime, referred to many research fields, this part research work is involved of powder metallurgy, hydromechanics, porous media mechanics and laboratory experiments.The main researches of this dissertation are as follows:The theory and application of various kinds of laboratory permeability measurement methods have been summarized. The advantages and disadvantages of various kinds of laboratory permeability measurement methods have been analysed. In order to meet the needs of spacial permeability measurements, which is required to be flexibility in situations of multi-time-scale, large-range-changing, high efficiency and steady-going, a new kind of permeability measurement method has been proposed, which is remarkable for its features of rapid, large-range and high accuracy. This new method is based on the advantages of unsteady flow and testing fast of the traditional transient pulse technique. （Chapter 2 and 3）The development history of the traditional transient pulse method theory and its related parameters have been analysed. The key points and matters needing attention for the transient pulse permeability measurement experimental design have been summarized when the permeability parameter solved by using approximate solution. The experimental system and device structure design for storage-variable transient pulse method have been outlined. （Chapter 3 and 4）Based on inspiring from the theory of the traditional transient pulse method, breaking through the limitation of the narrow testing range, combining with the key points for experimental design with a great deal of testing experiences, the storage-variable transient pulse permeability measurement method and its testing device have been developed successfully. The new method has been proved availably and steadily by theory and practice. （Chapter 4）In view of the advanced permeability measurement method, named storage-variable transient pulse method, there has been conceived another kind of measurement method for testing ultra low permeability and also its matched system and device design trends. The ultra-low permeability measurement method can measure 10^-10D materials, such as halite, argillite and so on, moreover, it can make tests under high pore-pressure situations even more than 20MPa, so as to simulate complex geological processes in situ, under which it can be capable to obtain the permeability parameter of rock materials and its changing ragularities.（Chapter 4）13 kinds of the methodological and technological error sources have been discussed for storage-variable transient pulse technique permeation experiment. All the error sources have been classified to 6 kinds of error factors which make a great impact on measurement testing results. The impactions have been analysed categorically and systematically by using FEM numerical simulation method. It will help to optimize the testing operation, improve the testing device and supply an available reference to calibrate error influences. （Chapter 4）The influences, effected by the properties of rock specimen, the components of experimental system, the machinery and performance of testing device on the permeability measuring accuracy, have been analysed comprehensively. Presently, the accuracy of permeation experiment testing results cannot be illuminated definitely. In order to filling the gap of calibrating the accuracy and range availably for permeation measurement techniques, the conception of calibrating permeation experiment has been proposed, the conception of the standard sample for calibrating permeation experiment has been proposed and the detail design plan has been made. （Chapter 5）Applying the powder sintering technique to make porous media specimen by using powder sintering method, and considering the relations among various physical characteristics parameters of porous media materials, Li’s samples have been designed and manufactured successfully. The permeabilities of Li’s samples are constant and changeless under long-period and many different loading conditions permeation experiment testing. According to the permeabilities of Li’s samples, which are regarded as references, will help to supply a convincing check platform for permeation measurement fields. （Chapter 5）The calibration method for evaluating permeation experiments has been drafted up within Li’s samples applications. It will help to establish the unified standards and checking platform for permeability measurement techniques. （Chapter 5）更多还原