西安市城市内涝模拟与损失灰色关联度研究

Study on urban interior simulation and grey correlation degree of simulation and loss in Xi’an City

综合GIS技术与城市内涝基本原理,基于DEM、水文学原理、不透水面并考虑下渗、排水情况,模拟水流沿格网单元从高到低流动,按照坡度比例分配流量,形成不同降雨强度的城市内涝情景模拟,提取西安市几个典型的积水点淹没风险范围和分布特征等信息,并进行空间分析与数据验证,结果与实际相符。再叠加地表覆盖分类成果和统计年鉴数据,获取不同淹没风险范围内的人口、经济、交通、建筑物等数据,引入灰色关联理论对降雨量和损失因子的关联程度进行定量化,探讨综合影响因素中城市内涝损失的大小问题。结果表明:降雨量与经济损失因子的关联度最大,达到了0.823,与人口损失因子的关联度最小,为0.725,从大到小的顺序为:经济>建筑物>淹没面积>道路>人口。因此,提出充分考虑人为可控的城市内涝影响因子,合理控制城市用地扩展速度,提高土地利用效率的建议,旨在对城市内涝的管理、预测、决策等提供参考。

Based on DEM,hydrology principle,this paper synthesizes the basic principles of GIS technology and urban intrinsic,impervious surface and considering infiltration and drainage,simulates water flow along the grid unit from high to bottom,distributes flow according to slope ratio,and forms the urban interior scenario simulation in different rainfall intensity,which extracting information such as the risk range and distribution characteristics of typical water points in Xi’an.The spatial analysis and data validation results are consistent with the actual results.Superimposed surface coverage of classification results and statistical yearbook data include population,economy,traffic,buildings,it get different risk of inundation,then introduce grey correlation theory to quantify the degree of correlation between rainfall and loss factors,and to explore comprehensive influencing factors of the intrinsic loss in the city.It shows that the correlation between rainfall and economic loss factor is the largest,reaching 0.823,and the correlation with the population loss factor is the smallest,reaching 0.725.The order from large to small is:economy>building>Inundation area>Road>Population.So,fully considering the artificially controllable urban intrinsic impact factor,it proposes to reasonably control the urban land expansion speed and improve land use efficiency,aiming at providing reference for the management,prediction and decision-making of urban inland.