高坝水库放空要求及设施设计研究

高坝水库调节能力强，在流域梯级开发和防灾减灾中发挥重要作用，但其面临的风险也客观存在，一旦失事后果不堪设想。水库放空或降水位能力是经济社会发展新阶段对大坝风险防控和应急管理提出的新要求。本文给出水库放空的定义、目的及分类，系统阐述了放空水头比、放空库容比、库水位降速等水库放空能力评价指标，梳理了国内外对水库放空的要求，选取我国25座典型高坝水库进行放空能力分析。结果表明：高坝水库放空水头比介于17.5%~71.8%，均值为42.7%；放空库容比介于47.2%~99.2%，均值为81.7%；放空时间介于7.2~123 d，均值为42.7 d；库水降速介于0.71~9.03 md，均值为3.0 md。从实践来看，高坝水库放空能力受总库容、放空水位、坝型等工程特性参数影响，也受河流形态、河谷形状和库盆特点等因素影响。据此对水库放空设施设计中的入库流量、放空指标、启动条件和分级决策模式等关键问题进行了分析，对我国水利水电工程行业水库放空设施设计和应急管理有一定参考意义。

Study onempting requirements and facility design of high dam reservoirs

The large reservoir with high dam has strong regulating capability,which plays a key role in the river cascade development,and disaster prevention and mitigation.However,the risk for the high dams also exists objectively,and once the dam breaks,the consequences are unimaginable.The capability of reservoir emptying or drawdown water level is a new requirement for the safety management of high dams by the national emergency management in the new stage of socioeconomic development.This paper puts forward the definition,purpose and categories of reservoir emptying,systematically states the evaluation indicators of reservoir emptying capacity such as reservoir emptying,emptying water head ratio,emptying water storage ratio,and drawdown rate of water level based on projects practice,summarizes the emptying and drawdown design requirements of reservoir both in China and abroad,and analyzes the emptying capacity of 25 typical reservoirs with high dam in China.The results show that,the emptying water head ratio of high dam and large reservoirs ranges from 17.5% to 71.8%,with an average value of 42.7%;the emptying water storage ratio ranges from 47.2% to 99.2%,with an average value of 81.7%;the emptying time ranges from 7.2 to 123 d,with an average value of 42.7 d;The drawdown rate of reservoir water is between 0.71 and 9.03 md,with an average value of 3.0 md.It shows that the emptying capacity of high dams not only mainly depends on design indicators such as total storage capacity,emptying water level,and dam type and so on,is also affect by river morphology,valley shape,and reservoir basin characteristics.Based on the above mentioned,the key issues in the design of reservoirs emptying facilities such as selection of inflow water,determination of emptying indicators,start-up conditions,hierarchical decision-making mode are analyzed.It has certain reference significance for the design and emergency management of reservoir emptying facilities in the future.