摘要
南水北调中线工程在冰期输水过程中宜采用冰盖下输水的方式,输水过程中维持冰盖稳定性成为输水成功与否的关键。鉴于输水渠道和天然河道的冰盖稳定性不同,本文以真冰为试验对象,开展了冰盖减压试验和冰盖增压试验,研究了冰盖稳定性与冰盖下水压力之间的关系。研究发现随着冰盖宽度的增加,冰盖下极限水压力升、降幅度先增大,后减小;而随着冰盖厚度的增加,冰盖下极限水压力降幅减小,升幅增大。同时由于冰盖对于水压力上升的承受能力显著强于水压力下降。为此,建议稳定冰盖形成后,应适当调高水位运行,以利于保持冰盖稳定性。
The mode of water conveyance under ice cover is suitable to be adopted for the water conveyance of the Mid-Route of the South-to-North Water Transfer Project during the ice period; for which the maintenance of the stability of the ice cover during the water conveyance becomes the key-link of the success of the conveyance. In view of the difference between the stabilities of both the water conveyance channel and the natural river channel, the decompression and supercharging tests for ice cover are made herein by taking the real-ice as the testing object for studying the relationship between the stability of ice cover and the wa- ter pressure under ice cover. The study finds that the increasing and decreasing ranges of the ultimate water pressure under ice cover are to be enlarged at first and then reduced along with the increasing of the width of ice cover, while the decreasing range is to be reduced and the increasing range is to be enlarged along with the increase of the thickness of ice cover for the ultimate wa- ter pressure under ice cover. At the same time, the bearing capacity against the increase of the water pressure under ice cover is significantly higher than that against the decrease of the water pressure. Therefore, it is suggested that the water conveyance is necessary to be carried out under the operation condition with a suitably increased water level after the formation of a stable ice cover, so as to keep the stability of the ice cover.
出处
《水利水电技术》
CSCD
北大核心
2011年第10期132-136,共5页
Water Resources and Hydropower Engineering
基金
国家杰出青年基金(50725929)
国家自然科学基金创新研究群体科学基金(51021004)
教育部"长江学者和创新团队发展计划"创新团队(IRT0851)资助
关键词
冰期输水
冰盖
稳定性分析
水压力变幅
南水北调中线工程
water conveyance during ice period
ice cover
stability analysis
changing range of water pressure
Mid-Route of South-to-North Water Transfer Project
