基于风险分析的路基设计洪水频率标准研究

Risk-based Study of Flood Frequency Standard for Highway Subgrade

为制定科学合理的路基洪水设防标准,并为公路技术标准的修订提供理论依据,研究了路基洪水设防标准的制定方法和理论依据。在建立路基洪水风险评估模型的基础上,寻找近期与远期社会经济效益的平衡点,制定适合中国的技术标准。分析了全国水文特征的分异规律,将全中国分为3个大区,并结合中国社会经济发展现状、公路等级、地貌特征,根据风险模型提出了路基设计洪水频率标准框架,为标准修订提供理论依据。研究结果表明:仅由洪水频率控制的设防标准不能实现路基设防标准的统一,应当根据风险承受水平和水文特征制定标准。

To develop scientific and reasonable flood control standards of subgrade, and provide theoretical basis for upgrading the provisions in the technical standards for highway engineering, this paper studied the theory and method of flood control standard-setting for subgrade design. We put forward a risk assessment model to look for the balance between the immediate and long- term social and economic benefit to develop flood control standards in China. By analyzing the rainfall characteristics in China, this paper made a scheme of 3 zones to express the different hydrological characteristics all over the country. The new standards frame was proposed according to the results of risk analysis, the social and economic development degree, road grade and topographical features. The results show that highway flood control level in the country could not keep the unification only by flood frequency control standard. The upgrading version should be also formulated according to the acceptable risk level and the hydrologic characteristics.