中文摘要：

开河前，冰盖糙率增加造成渠道水位上涨，有武开河的可能，易形成冰坝；开河时的水力半径和综合糙率突变造成渠道水位陡降，存在渠道衬砌破坏的危险。本文通过分析渠系融冰期的水力响应特性，从渠系运行安全（水位波动幅度和波动速率较小）角度提出渠系融冰期安全输水模式——适时适量的调节各分水口取水量，基于冰情预报建立了渠系融冰期自动化控制管理模型。该模型在渠系安全高效运行的基础上可加快渠系由冰期输水转为正常输水的过程，增大了渠系的输水效益。融冰期的冰盖糙率变化过程是影响渠系水位波动和流量调节量的重要因素，需要通过不同气象条件和流量下的详细原型观测进行分析。

英文摘要：

Water level fluctuaes in a big range during ice mehing period caused by the changes of rough- ness and thickness （hydraulic radius） of ice cover, with more possibility of ice jam formation. To protect canal system from ice disaster and reduce the ice melting period, the flow target of canal system should be adjusted, and a mathematical model is obtained based on ice condition prediction to direct the automa- tion operation of canal system in this paper. The model is used for canal system security, and canal sys- tem can be free flow earlier and more water can be transport to downstream users. The changing process of ice cover roughness is very important to this model to improve the hydraulic response of canal system; which should be obtained by long term ice observations.