Differential Ground-Based Radar Interferometry for Slope and Civil Structures Monitoring: Two Case Studies of Landslide and Bridge

Abstract

Ground-based radar interferometry, which can be specifically classified as ground-based synthetic aperture radar (GB-SAR) and ground-based real aperture radar (GB-RAR), was applied to monitor the Liusha Peninsula landslide and Baishazhou Yangtze River Bridge. The GB-SAR technique enabled us to obtain the daily displacement evolution of the landslide, with a maximum cumulative displacement of 20 mm in the 13-day observation period. The virtual reality-based panoramic technology (VRP) was introduced to illustrate the displacement evolutions intuitively and facilitate the following web-based panoramic image browsing. We applied GB-RAR to extract the operational modes of the large bridge and compared them with the global positioning system (GPS) measurement. Through full-scale test and time-frequency result analysis from two totally different monitoring methods, this paper emphasized the 3-D display potentiality by combining the GB-SAR results with VRP, and focused on the detection of multi-order resonance frequencies, as well as the configure improvement of ground-based radars in bridge health monitoring.

Assessing blasting techniques in vibration sensitive areas at Kinross − Round Mountain to enhance blasting criteria

“…The majority of traditional blasting criteria involve the assessment of PPV [3][4][5][6][7] with some incorporating dominant frequency [3]. A major factor of PPV usage in blast vibration criteria is its convenience of measurement and ease of assessment [4].…”

“…Ground-based radar is able to detect movement with high accuracy [6] and is used in a variety of slope stability applications, including bridges and landslides [7], volcanoes [8], natural and engineered slopes [9] and mining applications [10]. The majority of mining applications in the literature involve discussions of radar for overall slope monitoring [6] and the applications for analyzing blasting with radar are scarce.…”

A Review on Low-Cost Microwave Doppler Radar Systems for Structural Health Monitoring

“…During onsite testing, these sensors are typically mounted on a tripod and pointed towards bridges, landslides, towers, and dams . The main difference between GBIR and other portable radar sensors is their relatively large detection range due to the use of bulky, high directivity antennas and waveguide-based components [38]. By transmitting and receiving electromagnetic waves at microwave frequencies, they can remotely detect small displacements of targets using the interferometric technique, and they are also able to distinguish the real displacement of targets of interest from clutter since the vast majority of GBI radar systems employs stepped-frequency continuous-wave (SFCW) or frequency-modulated continuous-wave (FMCW) radar sensors.…”

Integration of Digital Image Correlation of Sentinel-2 Data and Continuous GNSS for Long-Term Slope Movements Monitoring in Moderately Rapid Landslides

“…A wide range of techniques is nowadays available for monitoring slope movements: (i) in situ instrumentation such as inclinometers, wire extensometers, crackmeters, seismic sensors and Global Navigation Satellite Systems (GNSS) [1][2][3][4][5]; (ii) proximal sensing systems such as Terrestrial Laser Scanner (TLS), Ground-Based Synthetic Aperture Radar (GB-SAR) and Automated Total Station (ATS), which allow us to obtain spatialized data using a single acquiring sensor [6][7][8][9][10]; (iii) unmanned aerial vehicles (UAV) that are able to deliver spatially distributed information at a relatively low cost [11][12][13][14][15];…”