水利水电科技进展
水利水電科技進展
수이수전과기진전
ADVANCES IN SCIENCE AND TECHNOLOGY OF WATER RESOURCES
2014年
6期
56-61
,共6页
三维水沙模型%平衡输沙率%河势%河床变形%治导工程%永定河
三維水沙模型%平衡輸沙率%河勢%河床變形%治導工程%永定河
삼유수사모형%평형수사솔%하세%하상변형%치도공정%영정하
three-dimensional flow-sediment model%equilibrium transport rate%river regime%riverbed variation%training structure%Yongding River
为了检验永定河现状治导工程能否有效控制河势，采用CREST三维水沙数值模拟系统模拟分析河势走向、水沙浓度以及河床变形。根据永定河卢梁段河流泥沙和河床变化特征，引入合理床面悬移质平衡输沙浓度、推移质平衡输沙率以及平面分配系数，建立永定河卢梁段三维水沙模型并进行河床变形验证；模拟分析了河道流速场分布、悬沙浓度分布及河床变形规律，以及现状治导工程在控导河势方面发挥的作用，得到了河道环流、丁坝头绕流等复杂水流规律，并对游荡型河道流势、流向和顶冲点位置以及洪水主槽冲刷、边滩丁坝保护区淤积情况进行了预测。分析结果表明，河道治导工程在控制河势方面依然起到主导作用，部分丁坝坝顶受漫流冲刷破坏，局部河道需要添加少量短丁坝以巩固堤防安全。
為瞭檢驗永定河現狀治導工程能否有效控製河勢，採用CREST三維水沙數值模擬繫統模擬分析河勢走嚮、水沙濃度以及河床變形。根據永定河盧樑段河流泥沙和河床變化特徵，引入閤理床麵懸移質平衡輸沙濃度、推移質平衡輸沙率以及平麵分配繫數，建立永定河盧樑段三維水沙模型併進行河床變形驗證；模擬分析瞭河道流速場分佈、懸沙濃度分佈及河床變形規律，以及現狀治導工程在控導河勢方麵髮揮的作用，得到瞭河道環流、丁壩頭繞流等複雜水流規律，併對遊盪型河道流勢、流嚮和頂遲點位置以及洪水主槽遲刷、邊灘丁壩保護區淤積情況進行瞭預測。分析結果錶明，河道治導工程在控製河勢方麵依然起到主導作用，部分丁壩壩頂受漫流遲刷破壞，跼部河道需要添加少量短丁壩以鞏固隄防安全。
위료검험영정하현상치도공정능부유효공제하세，채용CREST삼유수사수치모의계통모의분석하세주향、수사농도이급하상변형。근거영정하로량단하류니사화하상변화특정，인입합리상면현이질평형수사농도、추이질평형수사솔이급평면분배계수，건립영정하로량단삼유수사모형병진행하상변형험증；모의분석료하도류속장분포、현사농도분포급하상변형규률，이급현상치도공정재공도하세방면발휘적작용，득도료하도배류、정패두요류등복잡수류규률，병대유탕형하도류세、류향화정충점위치이급홍수주조충쇄、변탄정패보호구어적정황진행료예측。분석결과표명，하도치도공정재공제하세방면의연기도주도작용，부분정패패정수만류충쇄파배，국부하도수요첨가소량단정패이공고제방안전。
In order to examine whether the training structures could effectively control the river regime or not, a three-dimensional (3D) model CREST is applied to analyze the river regime trend, sediment transportation, and river bed deformation of Yongding River. According to the characteristics of sediment and riverbed variation of Lu-Liang section of Yongding River, a 3D numerical model is set up with a proper equilibrium concentration of suspended load, the bedload transport rate, and plane partition coefficient. The model is calibrated by bed deformation. Then, the rule of training structures played in controlling the river regime is studied by simulating the velocity field, the sediment concentration distribution and bed deformation. As a result, complex flow laws of the vortex and the spur dike flow are obtained. Additionally, the flow tendency, flow direction, scouring point location, erosion in main channel due to flood, and deposition owing to spur dike protection are predicted. The 3D numerical model is applied to simulate the river regime variation, sediment transport, and bed deformation of Yongding River. The results show that long spur dikes control the river regime, and some of them are suffered from overflow and local scour on the head. For levee safety, short groins need to be added to some local river banks where the erosion often happened.
