To understand the hydromechanical behavior of jointed rock masses, the study of isolated rock joints is a key element. Nowadays many scientists stand for taking joints' morphology into account. In order to get numerical model for these joints, we propose an original method based on the use of the geostatistical tools. Using them allows to analyze the spatial relations between elevations (sampled from the joint), and their first and second derivatives. Next we present a method for the reconstruction of a fracture surface by using a variogram model derived from data coming from two different samples located on the same fracture a few centimeters apart. The method of reconstruction is performed in several steps in order to have a more and more accurate reconstruction. Finally, at?er the validation of the reconstructions by different ways, we show the implications of the size of digitalization of the fracture surfaces and of the kinds of reconstruction on the results of simulation of shear tests.
The knowledge of the hydromechanical behavior of jointed rock masses is today very important in a lot of environmental problems (waste storage, rock mass stability, high enthalpy geothermal reservoirs, etc.). The study of jointed rock masses requires the study of isolated rock joints. It is well known that the morphology, the roughness of a joint is a key element for the understanding of its hydromechanical behavior. The aim of this paper is to show how very accurate numerical models of fracture surfaces can be inferred from quite unusual geostatistical methods and then successfully used in mechanical modeling.
