A unified framework for engineering characterization of argillaceous formations (soils and rocks)

泥质地层（土壤和岩石）工程表征的统一框架

• 批准号: RGPIN-2015-06703
• 负责人: Wong, Ron
• 金额: $ 1.46万
• 依托单位: University of Calgary
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=614309
• 关键词: unified; framework; engineering; characterization; argillaceous

Argillaceous formations are the most abundant sedimentary soil and rock types, varying according to different estimates from 45 to 55% of the total sedimentary formation column. The argillaceous formations containing silt- or clay-sized particles or clay minerals could be uncemented (stiff clays and hard clays) or hardened (shales, argillites, siltstones, and mudstones). Due to their abundance and variation in engineering properties, the argillaceous formations impose many challenges on the geotechnical community (e.g., foundation, slope stability, and underground excavation) and energy sector (e.g., well completion, reservoir containment, and hydraulic fracturing).     All these argillaceous formations are composite equivalents of clays, muds, and silts, with varying degree of consolidation or cementation (induration). Their engineering properties depend on constituent type, composition, size distribution, arrangement, and cementation. Most of previous research investigations on argillaceous formations are very site specific. Empirical correlations based on simple physical tests indices (such as clay content, liquid and plastic limits) have been made among argillaceous formations from different sites. These empirical correlations have no room for scientific development and limiting use in engineering practices. The long-term goal of this proposed research program is development of a unified framework for engineering characterization of argillaceous formations (soils and rocks). The framework will be built on understanding and quantifying the fundamental physics of the nano- and micro-structures of the argillaceous formations, and the interaction of the composite materials with the environmental changes encountered in practical applications. Advanced imaging and microscopy techniques will be used in characterizing the argillaceous formation structure in nano- and micro-levels. Innovative methodologies will be developed in laboratory to evaluate the behavior and performance of argillaceous formations under high temperature, pressure, stress and chemical gradient conditions in practical applications. The findings from this research program can be readily transferred to other research and practical activities listed above in terms of constitutive modelling, numerical simulation and design.

泥质地层是最丰富的沉积土壤和岩石类型，根据不同的估计，占总沉积地层柱的 45% 至 55%。含有粉砂或粘土大小的颗粒或粘土矿物的泥质地层可以是未胶结的（硬粘土和硬粘土）或硬化的（页岩、泥岩、粉砂岩和泥岩）。由于其丰富性和工程特性的变化，泥质地层给岩土工程界（例如地基、边坡稳定性和地下开挖）和能源部门（例如完井、油藏围堵和水力压裂）带来了许多挑战。     所有这些泥质地层都是粘土、泥浆和粉砂的复合物，具有不同程度的固结或胶结（硬结）。它们的工程特性取决于成分类型、组成、尺寸分布、排列和胶结。先前对泥质地层的大多数研究调查都是针对特定地点的。基于简单的物理测试指数（例如粘土含量、液体和塑性极限），我们在不同地点的泥质地层之间建立了经验相关性。这些经验相关性没有科学发展的空间，并且限制了在工程实践中的使用。该研究计划的长期目标是开发一个统一的泥质地层（土壤和岩石）工程表征框架。该框架将建立在理解和量化泥质地层纳米和微米结构的基本物理原理以及复合材料与实际应用中遇到的环境变化的相互作用的基础上。先进的成像和显微镜技术将用于表征纳米和微米水平的泥质地层结构。将在实验室开发创新方法，以评估实际应用中高温、高压、应力和化学梯度条件下泥质地层的行为和性能。该研究项目的研究结果可以很容易地转移到上面列出的本构建模、数值模拟和设计方面的其他研究和实践活动中。