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

Geometry of the rock joint is a governing factor for joint mechanical and hydraulic behavior. A new method of evaluating aperture distribution based on measurement of joint surfaces and three dimensional characteristics of each surface is developed. Artificial joint of granite surfaces are measured,processed, analyzed and three dimensional approaches are carried out for surface characterization. Parameters such as asperity's heights, slope angles, and aspects distribution at micro scale,local concentration of elements and their spatial localization at local scale are determined by Geographic Information System (GIS). Changes of aperture distribution at different normal stresses and various shear displacements are visualized and interpreted. Increasing normal load causes negative changes in aperture frequency distribution which indicates high joint matching. However, increasing shear displacement causes a rapid increase in the aperture and positive changes in the aperture frequency distribution which could be due to unmatching, surface anisotropy and spatial localization of contact points with proceeding shear

GIS Analysis of the Erosional Process of Volcanic Deposits in Inukai Area, Japan

The Aso volcanic deposits in Inukai area mostly consist of the Aso-4 pyroclastic flow deposit, which is divided into A4 and A4W. A4 overlays A4W and mainly composed of tuffs, whereas A4W, of welded tuffs. Erosional process of volcanic deposits may cause slope failure hazards requiring continuous monitoring in order to manage probable risk over people, surface affairs and infrastructure. Erosional process is studied by utilizing 1:50,000 geological map and, digital elevation model processed in geographical information systems (GIS). The present topographic surface was obtained from all the elevation points, whereas the contact surface between the A4 and A4W rock units was generated by utilizing spline interpolation involving only elevation points along the A4-A4W geological boundary. The present topography and the A4-A4W geological contact surface were performed to calculate the total thickness of A4 unit. Generally, the A4 rock units is characterized as poorly welded and lower resistance to abrasion than A4W, so the distribution would be constrained by regional erosion. GIS analysis has made it possible to evaluate the thickness distribution of the A4 rock unit and erosional process in this area. Comparison between these results and the distribution of slope failure risk zones (which were defined accordingly with the methodology to analyze high angle risk zones from the Japanese Ministry of Construction) would allow reclassifying slope failure risk zones

GIS Analysis of the Erosional Process of Volcanic Deposits in Inukai Area, Japan

The Aso volcanic deposits in Inukai area mostly consist of the Aso-4 pyroclastic flow deposit, which is divided into A4 and A4W. A4 overlays A4W and mainly composed of tuffs, whereas A4W, of welded tuffs. Erosional process of volcanic deposits may cause slope failure hazards requiring continuous monitoring in order to manage probable risk over people, surface affairs and infrastructure. Erosional process is studied by utilizing 1:50,000 geological map and, digital elevation model processed in geographical information systems (GIS). The present topographic surface was obtained from all the elevation points, whereas the contact surface between the A4 and A4W rock units was generated by utilizing spline interpolation involving only elevation points along the A4-A4W geological boundary. The present topography and the A4-A4W geological contact surface were performed to calculate the total thickness of A4 unit. Generally, the A4 rock units is characterized as poorly welded and lower resistance to abrasion than A4W, so the distribution would be constrained by regional erosion. GIS analysis has made it possible to evaluate the thickness distribution of the A4 rock unit and erosional process in this area. Comparison between these results and the distribution of slope failure risk zones (which were defined accordingly with the methodology to analyze high angle risk zones from the Japanese Ministry of Construction) would allow reclassifying slope failure risk zones

Analysis of Underground Block Caving Mining Induced Surface Movement in Papua, Indonesia

The occurrence of the surface movement is the main focus of the study regarding to the gold & copper underground block caving mining in Papua, Indonesia. The underground mining has brought some environmental problems on the terrain surface such as the lowering of the elevation followed by growing of the waste pile as the result from the failure of the rock slope. In this study, the surface movements due to the underground mining were analyzed by using the aerial photogrammetry method and the Geographic Information System (GIS) technology. The detected surface subsidence ranging from 1.5 to 2 meter and the development of the sedimentation area has been identified in which the maximum deposit thickness is about 2 meter. In addition, the correlations between extraction thicknesses over the overburden versus ground movement have been studied in order to find out the influence of some geological conditions in the development of the surface changing. The surface movement induced by underground mining causes some serious environmental impact not only above the extraction zones but also the surrounding areas. Some environmental impacts due to the surface movement are reviewed and discussed in this paper in order to describe the current situation of the underground mining in Papua, Indonesia