Optimized stress analysis model generation for tunneling applications incorporating geology

拟议的研究计划旨在开发一个自动生成优化模型的框架，用于结合地质特征的隧道应用中的应力分析。涉及岩土材料的建模和设计往往不得不适应我们缺乏知识或数据的情况，这主要是由于成本，特别是对于三维建模。在隧道设计中，地质特征不仅使开挖变得复杂，增加了成本，而且如果建模不当，可能会对结果产生重大影响，并可能导致不正确的设计。它们的影响主要是由于不同的材料特性(例如，刚度高3倍的侵入性堤坝吸引应力)。遗憾的是，在目前的应力分析实践中，由于缺乏建模工具和时间限制，地质学常常被省略。拟议的框架将使地质特征能够适当地包括在应力分析中，使用选择性算法来过滤不影响结果的特征。模型生成将需要输入参数，例如隧道几何形状和地质特征(例如接缝的方向和间距等)。隧道(S)的高分辨率表面网格将使用网格划分算法从输入数据自动生成，并将在包含地质特征的同时实现隧道交叉点的解析。该模型将根据申请人首创的感兴趣区域(ROI)概念进行优化，以降低网格密度并消除地质特征。生成的网格在ROI处将具有良好的质量，而在较远的区域将具有较低的密度。根据该网格，可以使用对有限元分析有用的三维网格划分算法来创建体网格。研究计划的下一步将涉及使用实际场景测试框架。与现有研究方案不同的是：在隧道模型中加入地质特征进行应力分析，并能够根据ROI自动生成优化网格，以减少计算时间，同时保持考虑地质特征影响的求解精度。该框架将使加拿大和世界各地能够设计出更安全、更经济的隧道和地下基础设施。

The proposed research program aims at developing an automated framework for optimized model generation for stress analysis in tunneling applications incorporating geologic features. Modeling and design involving geomaterials often has to accommodate for our lack of knowledge or data mainly due to cost, particularly for three-dimensional modeling. In the design of tunnels, geologic features not only complicate excavation and add to the cost, but if not modeled properly, can substantially influence the results and could potentially lead to incorrect design. Their influence is mainly due to differing material properties (e.g. an intrusive dyke with 3x higher stiffness attracting stress). Unfortunately, in current stress analysis practice, geology is often omitted due to lack of modeling tools and time constraints. The proposed framework will enable the proper inclusion of geologic features in stress analysis using a selective algorithm to filter out features not affecting the result. Model generation will require input parameters, such as tunnel geometry and geologic features (e.g. orientation and spacing of joints, etc.). A high-resolution surface mesh of the tunnel(s) will be automatically generated from the input data using meshing algorithms and resolution of intersections of tunnels will be implemented along with inclusion of geologic features. The model will be optimized to reduce mesh density and eliminate geologic features based on a region of interest (ROI) concept pioneered by the applicant. The generated mesh will have good quality at the ROI and reduced density at 'far away' regions. From this mesh, a volume mesh can be created with 3D meshing algorithms useful for FEM analysis. The next step of the research program will involve testing the framework using practical scenarios. What sets the proposed research program apart from the existing ones is: inclusion of geologic features in the tunnel model for stress analysis and the ability to automatically generate optimized meshes based on ROI to reduce computation time while maintaining solution accuracy considering the effect of geologic features. The framework will enable the design of safer and more economical tunnels and underground infrastructure in Canada and around the world.