基于Ward系统聚类方法的黄河上游干流地区滑坡分类及其特征分析

Classification of the landslides and analysis of their development characteristics in the upper reaches of the Yellow River based on Ward system clustering method

黄河上游干流地区滑坡分布广、规模大、体积大、突发性强,是我国乃至世界上非常有代表性的滑坡集中分布区。选取了坡顶、坡脚、岩性、长度、宽度、厚度、面积、体积、坡度、坡向、年均降雨量、日最大降雨量、原始斜坡坡高和原始斜坡坡度,采用Ward聚类分析法对126处滑坡样本进行分析,得到4类滑坡。在此基础上,分别统计分析了每类滑坡的各个指标的最大值、最小值、平均值和标准差,以定性和定量相结合的方法,分析了各类滑坡隐含的特征规律以及滑坡指标之间的相互联系。通过综合分析和对比得出了各个指标影响滑坡发育的显著程度,得出了滑坡的发育特征。并通过因子分析计算了各类滑坡的旋转成份矩阵,确定了影响各类滑坡发育的主次因素。研究结果表明:(1)第一类滑坡由坡顶和坡脚主导,坡顶在2 450~3 020 m,坡脚在1 980~2 905 m;(2)第二类滑坡发育主要受原始斜坡坡度控制,多数处于易发生滑坡的坡度范围30°~40°;(3)第三类滑坡主要受坡向和原始斜坡坡高的影响,多数滑坡位于阳坡,并且原始斜坡坡高在100~500 m;(4)第四类滑坡主要影响因素是坡度和日最大降雨量,坡体的坡度处于易发生滑坡的35°~37.5°范围内,滑坡所在区域的日最大降雨量大。研究结果证明Ward系统聚类对于该地区滑坡类型划分结果是有效的,具有一定的实用价值。

Landslides often bring destructive damage,and lead to huge economic losing and heavy casualties.Therefore,the study of landslide development characteristics has important scientific value and practical significance. Landslides distribution is wide,the volume is big,the scale is large,landslides occur suddenlyin the upper reaches of the Yellow River. It is the representative landslides concentrated distribution area in China and even in the world. Ward cluster analysis is used to analyze 126 landslide samples,four kinds of landslide are obtained. slope crest,slope toe,lithology,length,width,thickness,area,volume,slope gradient,slope aspect,average annual rainfall,daily maximum rainfall,the height of original slope and the original slope gradient are selected in this research. On this basis,the maximum,minimum,average and standard deviation of each kind of landslide are analyzed,Combining qualitative and quantitative methods,The hidden characteristic rules of each kind of landslide and the relationship among the landslide indicators are studied. Through comprehensive analysis and comparison,the significant degree of each index affecting landslides development is obtained,the landslides development characteristics are obtained. The rotation component matrixs of each type of landslide was calculated by factor analysis,And the primary and secondary factors affecting the development of landslides were determined. Research results show that：（ 1） The first type landslides are dominated by slope crest and slope toe of the landslides,The slope crests are between 2 450 and3 020 meters,slope toe from 1 980 to 2 905 meters;（ 2） The second type landslides are mainly controlled by original slope gradient. Most of them are located at a slope from 30 to 40 degrees,which is prone to landslide;（ 3） The third type landslides are mainly affected by the slope direction and the height of the original slope.most of these landslides are located on the sunny slope,the height of the original slope change 100 to 500 meters;（ 4） The main influencing factors of the fourth type landslides are slope gradient and daily maximum rainfall,The slope gradients are in the range from 35 to 37. 5 degrees,in which landslides generally easy occur. The maximum daily rainfall in the landslide area is large. The results show that Ward system clustering is effective for classification of landslide types in this area,It has certain practical value.