【作者】 赵新；

【导师】 练继建；

【作者基本信息】 天津大学 ， 水利水电工程， 2011， 博士

【摘要】 输水工程经过寒冷地区时，普遍存在着不同程度的河冰现象。河流封冻以后，将影响正常的发电和供水，缩短航期，增加水工建筑物荷载，影响河流泥沙的运动，尤其是冰塞、冰坝危害，会给国家和人民造成巨大的损失。加拿大、俄罗斯、美国、日本和北欧许多国家的河流和输水渠道都受到冰期输水问题的困扰。我国冰情较为严重的地区有：东北地区、新疆地区和黄河流域。南水北调中线工程纬度跨越范围大，由北亚热带湿润型气候区向暖温带半湿润气候区输水，必将面临更加严峻的冰期输水问题。针对大型输水工程，开展冰期输水相关研究十分必要。本文在总结前人研究经验和成果的基础上，以南水北调中线工程为研究对象，采用理论分析、模型试验和数值计算相结合的手段，在深入分析冰水力学的主要机理和过程的基础上，重点研究了输水工程冰期输水能力和冰害防治控制措施。主要成果包括：1、提出了静水、动水冰厚预测的辐射冰冻度日法，采用统一的公式描述冰厚生长、消融的全过程；综合渠道参数和冰的力学特性，提出维持输水渠道冰盖稳定性的水位变幅控制的新指标；南水北调中线工程在冰盖输水期水位允许变幅不超过20cm，日变幅不超过15cm。2、分析了冰盖增厚物理试验模型率，提出冰盖增厚物理模型试验宜按照重力相似准则进行设计；通过冻结模型冰模型试验，进一步揭示了大型输水渠道冰凌下潜机理和冰坝形成条件，提出了结冰期和融冰期冰凌下潜的判断准则。3、建立了考虑冰凌下潜和水力加厚、力学加厚冰盖形成过程的输水渠道冰期输水仿真模型。阐明了南水北调中线工程总干渠在结冰期、冰盖输水期和融冰期的输水能力，分析了加厚冰盖糙率和冰凌间渗流对输水能力的影响。4、研究了冰盖输水期渠道封冻长度比、冰盖糙率和闸门控制方式对输水渠道水力特性的影响；基于冰盖输水期冰盖稳定性的运行约束条件，提出了两点控制运行方法。5、以冻结模型冰为试验材料，以南水北调中线工程为原型，研究了输水工程冰期输水过程中：冰盖膨胀力、上拔力、平整冰和碎冰流撞击力的作用水平、影响因素和破坏形式。6、研制了双缆网式新型拦冰索，提升了输水渠道的拦冰效果；提出拦冰索拦冰效果的衡量指标及计算公式；分析了拦冰索锚固端拉力，提出了拦冰索布设的合理间距。更多还原

【Abstract】 It is common that river ice arises, in varying degree, from low temperature in somesections that flowing through cold areas. This phenomenon may bring many troublescharacterized by disturbing electric power generation and water division, shorteningshipping lines, increasing load of hydraulic structures, interfering river sedimentmovement, especially producing ice dam and ice jam which can cause enormouslosses to the nation and the people. Many natural rivers and conveyance channels inhigh latitude countries are suffering from such problems, typically including Canada,Russia, American and Japan. In China, Northeast region, Xinjiang region, and YellowRiver basin have been worst affected by the above–mentioned problems. Therefore,South-to-North Water Diversion project in China, with a long span of latitude fromthe north subtropical humid climate zone to the warm-temperate semi-humid climatezone, must meet more serious challenges from water division during the ice age. It isvery necessary to research relative problems for large-scale water division projects.On the basis of former research experiences and results, this paper, choosingSouth-to-North Water Diversion project as the research object, adopts acomprehensive research method integrated theory analyses, model experiments andnumerical calculations, deeply analyses the main mechanizations and processes of theice hydraulics, and further focuses on the water division capability in the ice age andice disaster prevention and control. The main research achievements include:1、 This paper provides a radiation degree-day method for ice thicknessforecasting which both adapts to hydrostatic conditions and hydrodynamic conditions.It is characterized by its unity that a formula can describe in detail the whole processfrom ice growing to melting. Moreover, the author proposes a new set of amplitudecontrol indexes of water level for keeping ice cover stability. In South-to-North WaterDiversion project, the allowable amplitude of water level should not exceed20centimeter, and the daily allowable amplitude should not exceed15during thefreeze-up phase.2、It is reasonable that the physical model of ice jam design with gravitysimilarity as the general principle, on the basis of analyzing on the related physicalmodel rate. Through the model experiments of real ice, this paper reveals the icesubmergence mechanism and the condition of ice jam formation, and further providesthe judgment criterions on ice submergence both in the ice-flowing phase and in theice-melting phase.3、This paper builds simulation models of water division in the conveyancechannels during the ice phrase based on the formation of ice jam from icesubmergence, hydraulic thickening and mechanical thickening. And then this papernot only clarifies respectively the water division capability in the ice-flowing phrase, in the freeze-up phrase and in the ice-melting phrase, but also analyses the effect onwater division capability from the roughness and the percolation of ice jam.4、This paper also analyses the effect on the hydraulic characteristics of theconveyance channels respectively from ice cover roughness, sluice gate control andthe freeze-up length ratio (freeze-up segment/the whole channel). Two controloperation methods are provided based on the operation constraint condition forkeeping ice cover stability in the freeze-up phrase.5、In the case of South-to-North Water Diversion project, this paper, choosingreal ices as experiment materials, respectively researches the effect level, theinfluencing factors, and the failure mode due to the three kinds of forces: expansiveforce of ice cover, uplift force of ice cover and impact force between integral ices andbroken ices6、The author develops the net-style ice boom with two axes which can advancethe intercepting effect, also proposes the measurement index and calculation formulafor judging intercepting effects, then analyses on the anchor end tension, and finallydetermines the reasonable distances of the ice booms更多还原