Research of the estimate of the slope failure of rainfall in the damaged ground by the Tokachi and Hyogoken-Nanbu Earthquakes by using ground penetrating radar and field emission type electron microscope

1995年的兵古县南部地震和德胜地震对丘陵地区造成了严重破坏。在丘陵地带的边缘发现了严重受损的地面。造成现代建筑严重损坏的原因是软土地基和垃圾填埋区。我们应用探地雷达（GPR）方法对地震中的滑坡进行了探测。利用带有100MHz天线的SIR-3000 （GSSI）对沿受损区域的多条探地雷达线进行了检测。在探地雷达剖面和张拉裂缝地表上发现了地下滑坡结构。构造在探地雷达剖面上的倾角不是平缓角。弱反射图像显示了含水的软地面。这幅弱图像位于滑坡区。因此，探地雷达方法可用于损伤地面的分析。六甲山陡坡分布广泛。这些陡坡是由风化较深的花岗质岩石构成的。用x射线衍射鉴定了陡坡上的蚀变矿物，以估计风化产物。利用EDXRF分析了深部斜坡中许多岩石的化学成分，以检查风化程度。在塌陷的陡坡上，易浸出是清澈的。淋溶趋势与风化程度一致。通过化学成分的检验，有可能定量地反映出陡坡风化的过程。x射线衍射结果表明，许多边坡破坏含有高岭石等风化矿物。从这些结果来看，它似乎是由暴雨引起的崩塌

The 1995 Hyogo-ken Nanbu and Tokachi Earthquakes had caused serious damages on the hilly land. Serious damaged grounds were observed on the margin of the hilly lands. The reason for this serious damaged modern buildings is soft ground and landfill area. We applied the ground penetrating radar (GPR) method for the landslide in the earthquake. Many ground penetrating radar lines along the damaged area were examined by using the SIR-3000 (GSSI) with 100MHz antenna. The landslide structures under the ground were found on the GPR profiles as well as ground surface of the tension cracks. The dip of the structures on the GPR profiles is not gentle angle. The weakly reflected images show the water-bearing soft ground. This weakly image is located in the landslide area. Thus, ground penetrating radar method is useful for the damaged ground analyses.The steep slopes are widely distributed in Mount Rokko. These steep slopes were composed of deep weathered granitic rocks. Altered minerals in the steep slopes were identified by X-ray diffraction to estimate of weathering products. Chemical composition of the many rocks in the deep slopes was also analyzed by using EDXRF to check the grade of weathering. In the collapre steep slopes, readily leachable is clear. The leaching tendency coincides with the grade of the weathering. It is possible that the examination by the chemical composition quantitatively shows the progresses of the weathering of the steep slopes. Many slope failures have weathered minerals such as kaolinite by using X-ray diffraction. From these results, it seems to generate a collapse by the heavy rainfa