地下埋设管道穿河段的洪水危险度评价

地下埋设管道下穿河流,由于不同河流的汇水面积、地形、降雨、下垫面条件等因素可存在较大差异,不同工程段遭遇洪水的危险程度不同,需要简单有效的方法进行洪水危险度评价。以陕京三线输气管道山西临县段为例,定量分析了每个管道穿河段的洪水风险因子,包括汇水区的面积、降雨、高差、形状、土地利用、植被指数等因子,穿河点的纵向比降和横向高差等因子。根据因子间的相关性和因子与穿河管段实际水毁次数间的相关性,选定了影响洪水危险度的三个核心因子。采用多元线性回归模型和Logistic回归模型建立了洪水危险度评估模型,并绘制了陕京三线山西临县段洪水危险度分布图。成果为管道运行安全防护措施的制定和实施提供依据,方法可为类似线状工程的洪水风险评价提供参考。

Flood threat assessment for cross-river sections of underground pipeline

Underground pipelines inevitably go across rivers. For different crossed rivers, large differences may exist in their catchment areas, topography, rainfall, underlying conditions and so on, and then their flood threat will vary among corresponding infrastructure segments. Therefore, a simple but effective assessment method for flood threat is urgently needed. In this paper, the section of the Shaanxi-Beijing Gas Pipeline in Linxian County, Shanxi Province was chosen for case study. Firstly, flood factors were quantified for each crossed river, including the area, rainfall, elevation difference, planar shape, land use, vegetation index of each river catchment, and the longitudinal slope and cross-sectional elevation difference of each cross-over region. Secondly, three key factors were selected after the cross-correlations among the factors and the relationships between each factor and the number of historical flood damage events were examined. Thirdly, the multivariate linear regression and logistic regression methods were used to establish a flood threat assessment model. Finally, the flood threat zoning map of the Shaanxi-Beijing Gas Pipeline in Linxian County was obtained. The result would provide a basis for the formulation and implementation of protection measures in pipeline safety management, and the method in this paper could be a reference for similar flood threat assessments of linear infrastructures.