基于GIS评价活动断裂对公路的影响——以宁夏地区为例

为了查清活动断裂对公路的影响，总结了宁夏地区9条全新世活动断裂的基本特征和活动性，确定了评价和预测活动断裂对公路工程影响的指标体系，并建立了分级标准。采用优先排序法对指标进行筛选和优化，运用主成分分析法确定权重，选用多级模糊综合评判法建立了评价模型。以ARCGIS9为平台，建立了宁夏地区活动断裂空间数据库，运用矢量叠加运算实现了宁夏地区活动断裂对公路影响的现状评价，运用栅格叠加运算实现了宁夏地区海原活动断裂带对公路影响的预测评价。预测结果表明，宁夏地区对公路影响大的海原活动断裂面积为12．34km2，占全区总面积的1．0％；影响较大的为271．28km2，占总面积的21．4％；影响中等的为400．05km2，占总面积的31．6％；影响小的为585．04km2，占总面积的46．0％。

Impact of Active Fault on the Highway Based on GIS --Taking Ningxia Region as an Example

In order to make it clear that the effect of active fault on highway, the activities and the basic characteristics of nine Holocene active fault of the Ningxia region are analyzed, assessment and forecasting index system of active fault on the highway project is determined, and classification standard is established. The indicators are screened and optimized, principal component analysis method is used to determine weight, multifuzzy comprehensive evaluation is selected to establishment the evaluation model. Based on ARCGIS9, the spatial database of active fault in Ningxia is built, the current effect of achieve faults on the highway is finished by vector overlap calculating and forecasting assessment of achieve faults of Haiyuan is calculated by raster overlay. The forecasting result is that the area of achieve faults of Haiyuan on the highway with significant influence is 12.34 km2 , and 1.0% of the total area of Ningxia; the area with relatively big influence is 271.28 km2 , and 21.4% of the total area; the area with middle influence is 400.05 kme, and 31.6% of the total area; the area with little influence is 585.04 km2 , and 46.0% of the total area.