Abstract:
This paper describes the measurement and analysis of the roughness of natural rock joints with the
aim of proceeding to their characterisation and comparison. Eight rock joints (corresponding to
sixteen surfaces) were scanned with a three-dimensional scanner. This was followed by the
description and characterisation of the surface roughness, as well as its reproduction and generation
using techniques such as fractal models and Fourier transforms. Shear tests under constant normal
load were performed, the joint surfaces were again scanned, and the resulting roughness surfaces were
compared allowing the evaluation of asperity breakage and surface wear. One of the joint specimens
was tested under several normal stresses, which allowed the estimation of its mechanical
characteristics, and was scanned after each test to evaluate the influence of the normal and shear load
on the variation of roughness.
The scans of the rock joints produced accurate numerical descriptions of their topologies, allowing
countless possibilities of future studies, such as the study of the matching of rock joints by the
numerical adjustment of bottom and top surfaces, the statistical and geostatistical characterisation of
rock joints or the degradation of roughness after normal and shear tests. This paper presents an
overview of the research work that is still under way.
