艰险山区简单路网地质灾害易损性评价

Geological Hazard Vulnerability Assessment of Simple Road Network in DifficultMountainousAreas

在艰险山区多灾环境条件下,公路网的易损性与公路自身属性和区域环境属性密切相关。因此,提出以公路单元易损度为评价指标,从地震动特征、地质环境条件、次生地质灾害特征和自身属性出发,建立了公路桥梁、隧道、路段边坡单元评价指标体系,并考虑公路单元失效的相关性,对公路线路易损性展开了评价,在该基础上提出了山区简单路网易损性评价方法以及易损性分级标准;最后以都江堰至映秀通道的简单路网为例进行了计算分析。其结果表明:都江堰至映秀通道的易损性为0.2142,易损等级为D,说明路网抵抗灾害的能力较弱,如遇重大地质灾害可能会受到严重损坏,导致交通中断。该计算结果与2008年“5·12”汶川8.0级特大地震中G213线都江堰至映秀公路和都映高速公路严重受灾程度相一致。

The vulnerability of highway network is closely related to the attributes of highway and regional environment in the difficult mountainous area.Therefore,the vulnerability of highway unit is proposed as the evaluation index.The evaluation index system of highway bridge,tunnel and slope unit of section is established based on ground motion characteristics,geological environmental conditions,characteristics of secondary geological disasters and its own attributes.Moreover,the correlation of highway unit failure also is evaluated considering.On these basis,the vulnerability evaluation method and vulnerability classification standard of simple road network in mountainous areas are proposed;Finally,the simple road network from Dujiangyan to Yingxiu(Du-Ying)is taken as an example to calculate and analyze.The results show that the vulnerability of Du-Ying simple road network is 0.2142,and the vulnerability level is D,indicating that the road network has a weak ability to resist disasters.In case of major geological disasters,it may be seriously damaged so that traffic interruption will be caused.The calculated results are consistent with the severe damage degree of Du-Ying section of G213 Highway and Du-Ying Highway in the 8.0-magnitude earthquake in Wenchuan on May 12,2008.