Rock Joint Surfaces Measurement and Analysis of Aperture Distribution under Different Normal and Shear Loading Using GIS

摘要

Geometry of the rock joint is a governing factor for joint mechanical andhydraulic behavior. A new method of evaluating aperture distribution based onmeasurement of joint surfaces and three dimensional characteristics of eachsurface is developed. Artificial joint of granite surfaces aremeasured,processed, analyzed and three dimensional approaches are carried outfor surface characterization. Parameters such as asperity's heights, slopeangles, and aspects distribution at micro scale,local concentration of elementsand their spatial localization at local scale are determined by GeographicInformation System (GIS). Changes of aperture distribution at different normalstresses and various shear displacements are visualized and interpreted.Increasing normal load causes negative changes in aperture frequencydistribution which indicates high joint matching. However, increasing sheardisplacement causes a rapid increase in the aperture and positive changes inthe aperture frequency distribution which could be due to unmatching, surfaceanisotropy and spatial localization of contact points with proceeding shear.