Early warning for rockfall incidents occurring on slopes along highways and roads is a vital safety practice for both
human lives and property loss. Monitoring systems mainly rely on laser scanners, distributed sensors and precision
geodetic measurements. In this study, close range terrestrial photogrammetry is evaluated towards rockfall incident
detection. Photogrammetry has been extensively used for 3D mapping and reconstruction of terrain and infrastructure
mainly due to its relatively low implementation cost, compared to the above mentioned approaches, especially when
using non-metric digital cameras. Yet, the underlying problems in terrestrial photogrammetry include processing time,
precision, night capturing limitations, and various errors, including occlusion, camera geometry, lighting, etc. In the
present paper, an experimental setup along with preliminary results of the terrain photogrammetry integration into an
operational slope monitoring scheme are presented. More specifically, assessment of the detection limitations are
provided in order to evaluate whether photogrammetry can constitute a cost-effective alternative for rapid surface and
change detection processes. In addition, since false alarm incidents cause extensive resource draining, their magnitude
and occurrence are also reported.
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