The term extended reality (XR) refers to a family of technologies that cover Virtual Reality (VR), Augmented Reality (AR), and Mixed Reality (MR). The main benefit of XR is that it can offer a new viewpoint on the surrounding environment by augmenting it with digital data and visualizations. Recent developments of XR enable its deployment for rock engineering applications, including underground tunnels. In this paper, we demonstrate two cases of the use of XR in an underground tunnel to display spatial information on the tunnel surface. One of the tunnels in the Underground Research Laboratory of Aalto University (URLA) was digitized using Structure-from-motion (SfM) photogrammetry. As a result, a high-resolution 3D point cloud and textured model of the tunnel were created. Next, the rock joint planes were obtained semi-automatically from the digitized rock surfaces. The results are then represented in their actual positions in the tunnel geometry. In the first case, we used VR to display the rock joint planes on the textured model of the tunnel. In the second case, the data was displayed in real-time in tunnel conditions through a mobile device. The results demonstrate that XR technology can be successfully used in underground construction to digitize the workplace and provide a new perspective on the work environment, which can potentially lead to an increase in safety and productivity.

扩展现实 (XR) 一词是指涵盖虚拟现实 (VR)、增强现实 (AR) 和混合现实 (MR) 的一系列技术。XR 的主要好处是它可以通过使用数字数据和可视化来增强周围环境的新视角。XR 的最新发展使其能够用于岩石工程应用，包括地下隧道。在本文中，我们展示了在地下隧道中使用 XR 来显示隧道表面空间信息的两个案例。阿尔托大学地下研究实验室 (URLA) 的其中一条隧道使用运动结构 (SfM) 摄影测量法进行了数字化。结果，创建了隧道的高分辨率 3D 点云和纹理模型。下一个，岩石节理平面是从数字化的岩石表面半自动获得的。然后，结果会以它们在隧道几何形状中的实际位置表示。在第一种情况下，我们使用 VR 在隧道的纹理模型上显示岩石节理平面。在第二种情况下，数据通过移动设备在隧道条件下实时显示。结果表明，XR 技术可以成功地用于地下建筑，以实现工作场所的数字化，并为工作环境提供新的视角，这可能会提高安全性和生产力。数据通过移动设备在隧道条件下实时显示。结果表明，XR 技术可以成功地用于地下建筑，以实现工作场所的数字化，并为工作环境提供新的视角，这可能会提高安全性和生产力。数据通过移动设备在隧道条件下实时显示。结果表明，XR 技术可以成功地用于地下建筑，以实现工作场所的数字化，并为工作环境提供新的视角，这可能会提高安全性和生产力。