权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Forest Slope Stability Analysis applied the Science of Complexity

森林边坡稳定性分析应用了复杂性科学

基本信息

批准号：
15580126
负责人：
OMURA Hiroshi
金额：
$ 2.11万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15580126/
关键词：
Complexity Landslide Fractal Self Organized Criticality Slope Stability Disaster Mapping Sediment Run Off 地すべり崩壊竹林森林斜面

项目摘要

Landslides are important natural hazard in the mountainous areas and the slope stability is also important issue. For landslide mitigation and land use restriction, it is important to detect moving directions and travel distances as well as to find out the susceptible slopes with appropriate indexes. Fractal dimension "D" and other technology based on the science of complexity is expected to provide an index of susceptible level of the landslide moving direction or overlapping ratio that are needed in the screening method for detail site investigation of landslide in order to designate the restriction area of land use or countermeasures. This "D" is a mathematical theory that describes the quality of complex shapes. Countermeasures planning for areas that has complicated and concentrated landslides with high fractal dimension should be able to cover holistic area. Areas that have single landslides scattered over wide region with low fractal dimension should only have a simple plan for … More each local landslides. On the other hand, moving (traveling) or deforming directions of individual landslides are often difficult to decide, although they have conspicuous importance to the mitigation measures or the restriction designation of landslide hazard areas. In this context, Fractal dimension of landslide group is estimated, comparing with landslide area density, and moving directions, in western Japan. Consequently, the fractal dimension "D" from the different grid orientations for each landslide ranges 1.05-1.35. The other important results are referred below.Optimum values of D that are obtained from minimum grid number covering landslide perimeters should be used theoretically for the accurate judgment.In the area of Tertiary, they have a rather clear trend that as the relief energy increases the fractal dimension value also increases. In the Mesozoic, the trend is not clear. There is a clear trend in both of the geology that as the area density and overlapping ratio increase the value of fractal dimension also increases. So fractal dimension can express the area density and the overlapping ratio of the landslide simultaneously. The higher the overlapping ratio increases, the more complex the traveling distance is and the more detail investigation for mitigation is needed.The moving direction doesn't have dear relation with D. However, it tends to decrease as D increases in the high D region. It suggests that moving directions are similar in landslide groups that have high D characteristics. Adding to that, in some districts landslides tends to move simply towards the bottom of valley with the direction angle of 76-94 degree against the valley.Concerning with the bamboo stands expanding, the special Fractal dimension D increases as it increases. Therefore, D also can be an important index of invasion of bamboo stands that cause devastation of the slopes. Less

山体滑坡是山区重要的自然灾害，边坡稳定性也是一个重要问题。在滑坡防治和土地利用限制中，确定滑坡的移动方向和移动距离，并利用适当的指标找出滑坡的易感边坡是十分重要的。基于复杂性科学的分形维数“D”等技术有望为滑坡详细现场调查的筛选方法提供滑坡移动方向或重叠率的易感程度指标，以确定土地利用的限制区域或对策。这个“D”是一个描述复杂形状质量的数学理论。滑坡复杂集中、分形维数高的地区的对策规划应能覆盖整体面积。对于单个滑坡分布较广且分形维数较低的地区，只需对每个局部滑坡进行简单的规划。另一方面，个别滑坡的移动（行进）或变形方向往往难以确定，尽管它们对减灾措施或滑坡危险区的限制指定具有显著的重要性。在此背景下，对日本西部滑坡群的分形维数进行了估算，并与滑坡面积密度和移动方向进行了比较。因此，各滑坡不同格网方向的分形维数D在1.05 ~ 1.35之间。其他重要的结果见下文。从理论上讲，为了准确的判断，应采用覆盖滑坡周长的最小格数得到的D的最优值。在第三系区域，它们有一个相当明显的趋势，即随着地形能量的增加，分形维值也随之增加。在中生代，这种趋势并不明显。两种地质特征都有一个明显的趋势，即随着面积密度和重叠比的增大，分形维数也随之增大。因此分形维数可以同时表示滑坡的面积密度和重叠率。重叠比越大，行进距离越复杂，需要进行更详细的减灾研究。移动方向与D的关系不大，但在高D区，随着D的增加，移动方向有减小的趋势。这说明在具有高D特征的滑坡群中，其移动方向是相似的。此外，在某些地区，滑坡倾向于简单地向山谷底部移动，与山谷的方向角为76-94度。随着竹林面积的扩大，特殊分形维数D也随之增大。因此，D也可以作为竹林入侵造成坡地破坏的重要指标。少