强降水持续过程对上海市内交通经济损失评估模型初探

Brief research on economic impact assessment model for Shanghai urban transportation under durative extreme precipitation

通过探讨极端降水与城市道路交通受灾损失之间的关系确定灾损函数曲线,首先构建城市道路积水排尽模型、积水持续时间模型,以及道路积水的经济损失评估模型等理论模型,再引入与道路抗涝能力相关的社会经济因子,最终构建了一个极端降水对道路交通造成经济损失的估算模型.经检验,该模型具有较好的模拟性能和适用性,且所需输入变量少,计算简便,适合地区经济损失的快速评估.从该模型出发,确定了上海地区逐年极端降水降水强度和总过程降水量的阈值,从而提出一个新的极端降水定义方法——随影响因子变化的固定阈值法,该方法突出了极端降水给社会带来灾害损失这一社会特性,与其他方法相比更具社会实用价值.

Estimation models of economic losses due to flood are established by combining drainage times of urban road waterlogging-theoretical models and economic loss assessment models,etc.And then the＂loss＂curves are determined by discussing the relationships between daily mean precipitation and economic losses of urban transportation departments.Some socioeconomic variables,which are closely related to the anti-flood capability of urban transportation departments,are adopted in the models in this paper.By model testing,the economic loss assessment model established in this paper shows good simulation performance and applicability.And it has simple computation,needs few input variables,and is suited for the rapid assessment of the economic loss of some region.Based on the models established in this paper,the thresholds of the precipitation intensity and the total storm precipitation of each year in Shanghai are calculated.And a new definition of extreme precipitation,called ＂fixed thresholds varying with the influence factors＂,is given.This definition underlines the socioeconomic character of extreme precipitation which would cause economic loss and possesses high social practical values compared with other definitions of extreme precipitation.