Stress modelling and rock support for hydro-electric water tunnels

水力发电水隧道的应力建模和岩石支护

• 批准号: 490640-2015
• 负责人: Tannant, Dwayne
• 金额: $ 0.44万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Engage Plus Grants Program
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=586555
• 关键词: Stress; modelling; rock; support; hydro

hydro-electric facility located 70 km southeast of Kitimat, British Columbia is an impressive feat of engineering due to both its scale and the remoteness of its location. The focus of this research are two 16 km long water conveyance tunnels, one operational and one partially complete. The first tunnel, T1, was completed in the 1950s, while T2 was partially excavated in the early 1990s. The mountainous topography in the area poses challenges for rock support design as the stresses around the tunnels vary widely along the tunnel alignment. Large variations in stress orientations and magnitudes were identified from 2D finite element stress models and these results corresponded to failure mechanisms observed on site. The proposed research has the following goals: 1) Further evaluate the expected stress conditions around the continuation of the T2 tunnel by constructing a large 3D stress analysis model covering the full length of both tunnels. 2) Incorporate predicted stresses at along the tunnel and data regarding lithology, ground water inflow, and discontinuities into a probabilistic prediction tool called a Bayesian Network. 3) Use the developed Bayesian Network tool to predict ground classes along the tunnel. 4) Use the ground classes to recommend appropriate primary and final rock support to maintain tunnel stability and in turn provide guidance on expected tunnelling costs and scheduling.

位于不列颠哥伦比亚省基蒂马特东南 70 公里处的水力发电设施是一个令人印象深刻的 由于其规模和位置偏远，堪称工程壮举。本次的重点 研究项目是两条 16 公里长的输水隧道，其中一条已投入使用，另一条已部分运行 完全的。第一条隧道 T1 于 20 世纪 50 年代竣工，而 T2 于 2017 年部分开挖。 20世纪90年代初。该地区的山地地形给岩石支护带来了挑战 由于隧道周围的应力沿隧道路线变化很大。大的 从二维有限元应力中识别应力方向和大小的变化 models and these results corresponded to failure mechanisms observed on site.拟议的 研究目标如下： 1) 进一步评估 T2 隧道延续部分周围的预期应力条件 构建覆盖两条隧道全长的大型 3D 应力分析模型。 2) 结合隧道沿线的预测应力和有关岩性、地下水的数据 流入和不连续性进入称为贝叶斯网络的概率预测工具。 3）使用开发的贝叶斯网络工具来预测隧道沿线的地面等级。 4) 使用地面等级来推荐适当的主要和最终岩石支撑，以维持 隧道稳定性，进而为预期隧道成本和调度提供指导。