A NEW METHOD FOR RECONSTRUCTIONS OF ROCK RELIEFS

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7105-99-5 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 12, 19-24 pp, DOI: 10.5593/sgem2017/12/S02.003

ABSTRACT

The irregularity of rock joints in rocky terrains contributes considerably to better mechanical stability of these terrains. The assessment of the stage of surface irregularities (asperities) of jointed surfaces in rock massifs plays an important role when shear strength of rock joints are evaluated. For this purpose it is necessary to analyze morphology of surface reliefs of rock joints. The digital replicas of surface reliefs are ideal tools for such a morphology analysis. This paper describes a new method for digital three-dimensional (3D) reconstructions of surfaces of rock joints whose sizes may amounts several centimeters up to several meters. This method is therefore applicable to small as well as large parts of rock joints and thus it may be used not only in laboratories but also in open fields. The device includes commercially available components on affordable financial level and thus it is especially convenient for small research groups whose financial possibilities are limited. The philosophy of the device is based on the sectional technique. This technique reconstructs the 3D reliefs by means of optical images that are captured subsequently in the vertical direction above the solid surface with a constant step. Stepping the camera vertically with a step that is smaller then the depth of optical field, a convenient set of optical sections may be obtained from which the sophisticated software creates the 3D relief.

Keywords: Rock joints, asperities, joint roughness coefficients, devices for 3D scanning, 3D reliefs of rock joints.