A new method for in-situ non-contact roughness measurement of large rock fracture surfaces
2003 (English)In: Rock Mechanics and Rock Engineering, ISSN 0723-2632, E-ISSN 1434-453x, Vol. 36, no 1, 3-25 p.Article in journal (Refereed) Published
This paper presents a new method for in-situ non-contact measurements of fracture roughness by using a total station (TS). The TS is a non-reflector geodetic instrument usually used for measuring control points in surveying and mapping. By using a special-developed program, the TS can be used as a point-sensor laser scanner to scan a defined area of the fracture surface automatically, in field or in laboratory, at a distance away from the target surface. A large fracture surface can be automatically scanned with a constant interval of the sampling points, both within a defined area or along a cross-section of the exposed rock face. To quantify fracture roughness at different scales and obtain different densities of the scanned points, the point interval can be selected with the minimum interval of I rum. A local Cartesian co-ordinate system needs to be established first by the TS in front of the target rock face to define the true North or link the measurements to a known spatial co-ordinate system for both quantitative and spatial analysis of fracture roughness. To validate the method, fracture roughness data recorded with a non-reflector TS was compared with the data captured by a high-accuracy 3D-laser scanner. Results of this study revealed that both primary roughness and waviness of fracture surfaces can be quantified by the TS in the same accuracy level as that of the high accuracy laser scanner. Roughness of a natural fracture surface can be sampled without physical contact in a maximum distance of tens of meters from the rock faces.
Place, publisher, year, edition, pages
2003. Vol. 36, no 1, 3-25 p.
roughness, waviness, primary roughness, fracture surface, geodetic non-reflector total station, laser scanning, large fracture surface, in-situ measurement, dimension
IdentifiersURN: urn:nbn:se:kth:diva-22189DOI: 10.1007/s00603-002-033-1ISI: 000180474800001OAI: oai:DiVA.org:kth-22189DiVA: diva2:340887
QC 201005252010-08-102010-08-10Bibliographically approved