滑坡强度与能级的概念辨析及评估方法探讨

A study of concept discrimination and assessment methods of landslide intensity and magnitude

以能量数值和空间分布作为主要区分依据,初步界定了滑坡强度与滑坡能级的概念范畴及其异同。在此基础上,分别以意大利和瑞士的单体滑坡能级评估及地震集中诱发群体滑坡的能级评估为例,综述了单体及群发滑坡的能级特征参数及其评估方法进展。简述了以滑坡产出特征评估为手段的单体滑坡强度评估技术方法;重点结合汶川地震重灾区的绵远河流域滑坡研究,分析探讨了基于滑坡密度计算的区域滑坡强度评估基本原理及关键技术问题,分别剖析了基于搜索邻域单元、流域斜坡单元、行政辖区单元及线路工程单元的滑坡点密度和面密度计算方法及流程,进而对比分析了不同评估单元及密度类型的区域滑坡强度评估技术方法的差异及其适用性,结果表明利用滑坡面密度进行区域滑坡强度评估相比利用滑坡点密度的情况更加准确可靠。

The concepts,similarities and differences of landslide intensity and magnitude are preliminarily defined based on energy numerical value and spatial distribution.Taking the Italian and Swiss landslide researching cases as examples,this paper reviews the parameters and methods of single landslide magnitude assessment.Landslide cluster magnitude assessment is also reviewed with cases regarding to seismic landslides triggered by a single earthquake.Intensity assessment methods of single landslide and landslide clusters are reviewed and discussed.Single landslide intensity assessment using landslide runout assessment means is briefly summarized.Taking seismic landslide research in the Mianyuanhe river basin in Wenchuan Ms 8.0 earthquake severely afflicted area as an example,this paper selectively analyzes and discusses the basic principles and crucial technologies of regional landslide intensity assessment based on landslide density calculation.Calculating processes of landslide point density and area density based on searching neighborhood element,watershed slope element,administration element and linear project element are respectively analyzed.Differences and applicability of regional landslide intensity assessment methods with different assessing elements and density types are discussed.The results indicate that regional landslide intensity assessment using landslide area density is more accurate and reliable than that of using landslide point density.