Determination of Extent of Excavated Damage Zone Around Mined Tunnels using Pre and Post Construction Pore-Water Pressure Response

利用施工前后孔隙水压力响应确定采矿隧道周围开挖损坏区域的范围

• 批准号: RGPIN-2017-05277
• 负责人: Elwood, David
• 金额: $ 1.46万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=650158
• 关键词: Determination; Extent; Excavated; Damage; Zone

* * * *** * Normal* 0* * * * * false* false* false* * EN-US* JA* X-NONE* * * * * * * * * * * * * * * * * * * * * * * * * ** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * **** /* Style Definitions */*table.MsoNormalTable* {mso-style-name:"Table Normal";* mso-tstyle-rowband-size:0;* mso-tstyle-colband-size:0;* mso-style-noshow:yes;* mso-style-priority:99;* mso-style-parent:"";* mso-padding-alt:0cm 5.4pt 0cm 5.4pt;* mso-para-margin:0cm;* mso-para-margin-bottom:.0001pt;* mso-pagination:widow-orphan;* font-size:12.0pt;* font-family:Cambria;* mso-ascii-font-family:Cambria;* mso-ascii-theme-font:minor-latin;* mso-hansi-font-family:Cambria;* mso-hansi-theme-font:minor-latin;* mso-ansi-language:EN-US;}****The containment of nuclear waste in deep geological repositories (DGR) is the preferred method for long-term disposal of spent nuclear fuel globally. The benefit of a DGR is the presence of both engineered and geological barriers that isolate the repository from the surrounding geological environment. The challenge; however, is that like any underground excavation, the surrounding host rock will be damaged during adit excavation known as the excavated damage zone (EDZ). Damage initiation and fracture propagation occurs with the crack intensity decreasing with distance from the tunnel wall, which has a direct influence on the in situ permeability of the host rock. Currently, assessment of the immediate and temporal changes within the EDZ is carried out through numerical simulation and in full-scale underground laboratories where field tests can be conducted. These underground laboratories rely on physical sampling of the host rock following excavation of test adits as well as non-destructive geophysical methods. Both of these methods have some limitations in their overall efficacy. None of these methods can fully characterize the temporal geomechanical properties of the EDZ on a real-time basis throughout the life of the test facility. ***Recent studies have demonstrated that the response of high resolution piezometers to barometric loading, often referred to as geolysimeters, can be used to characterize both the stiffness and hydraulic conductivity of deep shale aquitards (Smith et al.1,2). The overall goal of the proposed research program is to advance current methods to evaluate the development and extent of the EDZ around tunnels constructed in intermediate geomaterials. The short-term objectives involve conducting comprehensive fundamental and applied research to evaluate the potential use of geolysimeters to: (1) determine the change of the in situ stiffness with time and with distance from the tunnel wall (2) determine the change in the hydraulic conductivity of the host rock within the EDZ with time; and (3) extend the current knowledge of stress rotations during tunnel construction and the impact of the accompanying excess pore-water pressure (poroelastic) response on the overall size and shape of the EDZ. My long-term objective is to help place Canadians at the forefront of tunnel construction technologies and nuclear waste storage.***Knowledge gained from this research program will be a critical component in our ability to assess and bound the potential implications of the EDZ in various host rocks currently planned for DGR construction. The potential users of the results include nuclear management organizations, environmental protection agencies, industry, and governmental decision makers. The model improvements may also be adapted for use in DGRs, in Canada and worldwide, to help inform relevant decisi

* * * *** * 正常* 0 * * * * * 假*假*假* * en - us *是* X-NONE * * * * * * * * * * * * * * * * * * * * * * * * * ** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * **** /* 样式定义* / *表。MsoNormalTable* {mso-style-name:"Table Normal"；* mso-tstyle-rowband-size: 0;* mso-tstyle-colband-size: 0;* mso-style-noshow:是的;* mso-style-priority: 99;* mso-style-parent:“”;* mso-padding-alt:0cm 5.4pt；* mso-para-margin: 0厘米;* mso-para-margin-bottom: .0001pt;* mso-pagination: widow-orphan;*字体大小:12.0分;*字体类型:威尔士;* mso-ascii-font-family:威尔士;* mso-ascii-theme-font: minor-latin;* mso-hansi-font-family:威尔士;* mso-hansi-theme-font: minor-latin;* mso-ansi-language: en - us;****将核废料封存在深层地质储存库（DGR）是全球长期处置乏核燃料的首选方法。DGR的好处是工程和地质屏障的存在，将储存库与周围的地质环境隔离开来。所面临的挑战;然而，与任何地下开挖一样，在坑道开挖过程中，围岩也会受到破坏，称为开挖损伤区（EDZ）。随着与围岩距离的增加，裂缝强度逐渐减小，损伤起裂和裂缝扩展发生，直接影响围岩的原位渗透率。目前，通过数值模拟和在可进行实地试验的全尺寸地下实验室对经济开发区内的即时和时间变化进行评估。这些地下实验室依靠开挖试验坑道后对宿主岩石进行物理取样以及非破坏性的地球物理方法。这两种方法的总体效果都有一定的局限性。这些方法都不能在测试设备的整个生命周期内实时地完全表征EDZ的时间地质力学特性。***最近的研究表明，高分辨率压力计对气压载荷的响应，通常被称为地质压力计，可以用来表征深层页岩含水层的刚度和水力导电性（Smith等人1,2）。拟议研究计划的总体目标是推进现有方法，以评估中间岩土材料建造的隧道周围的经济开发区的发展和范围。短期目标包括开展全面的基础和应用研究，以评估地质测量仪的潜在用途：(1)确定原位刚度随时间和与隧道壁距离的变化；(2)确定EDZ内宿主岩石的水力导率随时间的变化；(3)扩展了隧道施工过程中的应力旋转以及伴随的超孔隙水压力（孔隙弹性）响应对EDZ整体尺寸和形状的影响的现有知识。我的长期目标是帮助加拿大人在隧道建设技术和核废料储存方面走在前列。***从该研究项目中获得的知识将是我们评估和确定EDZ在目前计划用于DGR建设的各种宿主岩石中的潜在影响的关键组成部分。这些结果的潜在用户包括核管理组织、环境保护机构、工业和政府决策者。该模型的改进也可适用于加拿大和世界各地的dgr，以帮助为相关决策提供信息