Small Scale Joint Surface Roughness Evaluation Using Digital Photogrammetry

作者：Mikael G. Nilsson, Catrin Edelbro, Glenn Sharrock · 发表于：Epubl LTU · 年份：2012 · 被引用次数：10 · 研究领域：3D Surveying and Cultural Heritage、Optical measurement and interference techniques、Infrastructure Maintenance and Monitoring

This paper presents a procedure on how photogrammetry by simple means can be used to create a joint surface profile using standard off-the-shelf equipment. The results are presented as a step by step instruction ranging from imaging of a rock sample to validation of the acquired data to preparation of a numerical model. Imaging is performed using a camera with a fixed lens in combination with the photogrammetry software 3DM CalibCam and 3DM Analyst. Surface data validation is carried out by means of laser scan in order to create a reference surface for local coordinate comparison to the photogrammetry data terrain model (DTM). The photogrammetry data is proven to be accurate on a scale smaller than one millimetre and a numerical shear-box model is prepared using the profiles as input. Surface evaluation show no clear indication that any part of the surface would be less accurately imaged due to directional bias as the areas of deviation are evenly spread across the sample. Profiles derived from photogrammetry are related to JRC. Calibration of the shear-box model is on-going; no numerical results are included in this paper.