Chiu, Y.C.Y.C.ChiuLo, P.C.P.C.LoWang, T.T.T.T.WangTAI-TIEN WANG2021-02-042021-02-042020Chiu, Y.C.;Lo, P.C.;Wang, T.T.https://www.scopus.com/inward/record.url?eid=2-s2.0-85084664423&partnerID=40&md5=4d685a640b70c1f975af6ee0510cd354https://scholars.lib.ntu.edu.tw/handle/123456789/547367Providing information regarding safety and structure maintenance during and after construction, monitoring is now an essential part of modern civil engineering. The case cliff is located on an abandoned old route of Suhua Highway in eastern Taiwan, where old Suhua Highway passes through a mountain ridge with single-line one-way old Heping tunnel. This research presents the variation of the cliff and the tunnel for about four years, including fine Digital Surface Models (DSM) of the cliff produced by Unmanned Aerial Vehicles (UAV) photos, and DSMs of old Heping tunnel from photogrammetry and laser scanning. Comparing DSMs of the cliff and the tunnel from two time stages, morphological variation of cliff and tunnel, lining crack evolution and information about a fallen rock wedge on tunnel roof was acquired. Digital Surface Models of the cliff and the tunnel were combined to generate augmented reality. Users may experience the visualized monitoring results, the evolution of spatial reality with time, and also be able to observe the variation of the above in a virtual environment with precise location and exact color. This case demonstrates how monitoring in geotechnical engineering is stepping into a whole new era of detailed survey combined with digital reality. © 2020 ISRM.[SDGs]SDG15Antennas; Augmented reality; Geotechnical engineering; Rock mechanics; Rocks; Unmanned aerial vehicles (UAV); User experience; Coastal cliff; Digital surface models; Highway tunnel; Laser scanning; Monitoring results; Morphological variation; Mountain ridges; Precise locations; Landformsconference paper2-s2.0-85084664423