多情景降雨-径流的巫山县公路洪灾预警研究

暴雨情景下，山区径流水位突涨、流速与流量骤变等易发生公路洪灾,对人民生命财产安全造成巨大威胁。以巫山县为例，在不同强度降雨阈值下对降雨-径流水文参数指标进行量化处理，全面分析了降雨与水位、流速、流量之间的关系，并在多情景降雨下，基于公路洪灾孕灾指标，构建了公路洪灾预警模型。研究结果表明：山区径流水位变化幅度大于流速，而在大暴雨及特大暴雨情景下（降雨临界值185 mm）,流速变化大于水位，在不同降雨阈值下，等级较低的河流更易发生公路洪灾，其水位空间变化更剧烈、效应范围更广；而流量与水位变化则对等级较高的径流影响更大，且河流等级越高变化越明显；巫山县公路洪灾易发程度介于轻度与重度之间，东北与西南部区域公路洪灾易发性强，且较为集中，西南部、东部与中部，公路洪灾易发程度介于重度与中度之间，西北部、中部与南部区，介于轻度与中度之间。该研究结果可为山区公路洪灾防治提供决策依据。

Flood warning of Wushan county highway based on rainfall and runoff under multi-condition

Under the rainstorm scenario, the sudden rise of runoff level, the sudden change of quantity of flow and flow velocity in mountain areas pose a great threat to people’s lives and property. Taking Wushan county as an example, this study quantifies the hydrological parameters of rainfall-runoff under different intensity rainfall thresholds, comprehensively analyses the conversion relationship between rainfall and water level, flow rate and discharge, and establishes a highway flood warning model by combining flood preparedness indicators under multi-scenario rainfall. The results show that the variation range of runoff water level in mountain area is larger than that of flow velocity. However, the variation of flow velocity is larger than that of water level under heavy rainstorm and extraordinary rainstorm, the critical value of rainfall is 185 mm. Under different rainfall thresholds, the lower-grade river is more likely to suffer from highway floods resulting in dramatic spatial variation of water level and wide effected area, while the higher-grade runoff is more likely to be influenced by the variation of discharge and water level; The degree of Wushan county highway prone to flood is between mild to high, with the high degree and concentrated distribution in northeast and southwest region, it is between high and moderate in southwest, eastern and central regions , the degree is between mild and moderate in northwest, central and southern areas. The research results can provide basis for making decisions on mountain highway flood prevention and control to ensure people’s life and property safety.