Rock Slope Geohazard Assessment and Mitigation to Protect People and Infrastructure

未来十年，由于人口增长以及新的天然气、石油和采矿开发，加拿大将在陡峭的地形上建设数十亿美元的新基础设施。在陡峭的岩坡和相关基础设施附近生活或工作的人暴露在地质灾害中。该研究计划的长期目标是改进地质灾害评估技术，并在地质灾害评估和设计适当的风险缓解措施之间建立缺失的环节，以减少与陡峭岩坡上的岩石坠落相关的损失。短期目标是解决目前陡峭岩坡风险管理中的三个缺陷。现有的地质灾害评估方法可能会花费太长时间，并可能使进行评估的岩土工程师面临不安全的现场工作。过于简单化的几何公式(在目前的建筑规范中)被用来定义可以安全建造的区域；这些公式没有考虑到诸如岩体质量和基础设施脆弱性等重要因素。加拿大已经引入了坡面网格化等新技术，但需要设计方法来指定如何使用这些技术。研究目标是： 1)通过使用无人机和测试无人机上各种传感器包的有效性，改进陡峭岩面的评估技术。一系列数码彩色相机将与激光雷达传感器和红外相机进行比较。 2)通过考虑岩体和斜坡几何因素以及建筑物的易损性，确定确定地块上建筑物安全位置的收进距离的基本原理。计算挫折的多标准方法将是对目前做法的重大改进。 3)建立锚网加固边坡的设计方法，通过全尺寸试验的数值模拟，提高对基本支撑-岩体相互作用的认识，从而超越目前使用的简单破坏机制/荷载假设。此外，设计将明确纳入目前在岩质边坡危险等级系统中获得的数据，但令人惊讶的是，这些数据并未用于支架设计目的。 对回缩距离的研究将导致划定在哪里建造是安全的，从而防止建造过于接近岩石路基的房屋以用于山坡住宅发展。对公路、铁路、露天矿等沿线岩质边坡进行锚网加固设计研究，将挽救生命，减少经济和环境损失。使用无人机快速安全地表征房屋、公路和铁路上方的悬崖的研究将使人们能够在发生斜坡失稳时更快速地做出反应，并及时做出疏散或重新开放运输路线的决定。

Billions of dollars of new infrastructure will be built in steep terrain in Canada over the coming decade due to population growth and new natural gas, oil, and mining developments. People living or working near steep rock slopes and the associated infrastructure are exposed to geohazards. The long-term objectives of the research program are to improve geohazard assessment techniques and to build the missing links between geohazard assessment and the design of appropriate risk mitigation measures to reduce losses associated with rock falling from steep rock slopes. The short-term objectives address three deficiencies in the current risk management for steep rock slopes. Existing geohazard assessment methods can take too long and can expose geotechnical engineers doing the assessment to unsafe fieldwork. Overly simplistic geometric formulae (in current building codes) are used to define areas where it is safe to build; these formulae do not consider important factors such as the rock mass quality and the infrastructure vulnerability. New technologies such as slope meshing have been introduced in Canada but design methods are needed for specifying how these should be used.  The research objectives are to: 1) Improve assessment techniques for steep rock faces by using drones and by testing the effectiveness of various sensor packages on drones. A range of digital colour cameras will be compared with lidar sensors and an infrared camera. 2) Develop a rationale to determine setback distances that define safe locations for a structure on a lot by incorporating rock mass and slope geometry considerations as well as building vulnerability. A multi-criteria approach to calculation of setbacks will be a significant improvement over current practices. 3) Create design methodologies for slope stabilization with bolted mesh that advance beyond the currently used simple failure mechanism/loading assumptions by improving knowledge of fundamental support – rock mass interactions through numerical simulation of full-scale tests. Furthermore, the design will explicitly incorporate data that are now acquired in rock slope hazard rating systems, yet astonishingly, not used for support design purposes. The research on setback distances will lead to delineation of where it is safe to build, thus preventing construction of homes located too close to rock cuts for hillside residential development. For rock slopes along highways, railways, and in open pit mines, the research on design of rock stabilization with bolted mesh will save lives and reduce economic and environmental losses. The research using drones for rapid and safe characterization of cliffs above homes, highways, and railways will enable more rapid response and timely decisions about evacuations or reopening of transportation routes when slope instability occurs.