【作者】 陈建；

【导师】 李义天；

【作者基本信息】 武汉大学 ， 水力学及河流动力学， 2007， 博士

【摘要】 水库的修建,是改变水资源时空分布不均的有效手段,是减少洪涝灾害、充分开发利用水资源系统的重要组成部分。水库兴利效益的发挥是通过水库调度来实现的,水库调度方式与水库淤积发展、分布以及最终的淤积平衡是密切相关的。本文运用数学模型结合实测资料分析,进一步研究了水库淤积发展的过程及冲淤平衡特征,水库调度方式对水库淤积发展及平衡的影响规律,侧重对水沙过程、淤积过程及变化机理的分析,并在此基础上对三峡水库现有调度方式进一步进行优化。主要成果包括:1、通过分析蓄清排浑运用方式下水库淤积的发展特征以及库区河道冲淤平衡特征可以看出,蓄清排浑运用情况下,水库淤积平衡后往往在年内的汛冲枯淤过程中保持多年的冲淤平衡,水库纵向淤积形态是否发生大的变化取决于低水位期水流的输沙能力是否可以把此时段的来沙以及高水位期淤下的泥沙排向下游。2、以三峡水库为例,运用数学模型计算分析了三峡水库淤积发展特征以及调度方案改变过程中部分关键因素对水库淤积影响的特点。蓄清排浑运用水库在一定水沙条件下,汛前及汛后一定范围内改变汛限水位持续时间或者正常蓄水位的小幅变动仅增大了蓄水期的淤积量,增大了汛期的走沙负担,只要没有超出汛期富裕输沙能力的范围,其最终结果只会改变水库的淤积过程,并不会改变最终的平衡状态。汛限水位持续时间的长短是否改变水库最终的淤积平衡状态,取决于有效冲刷期内是否可以把增加的淤积量冲掉。如果在有效冲刷期内不能把增加的淤积量冲掉,水库的淤积平衡必然产生改变。3、对三峡水库现有调度方式进行优化调度,研究其在满足防洪条件下的兴利效益以及对水库淤积的影响,结果表明,有选择的一定限度内缩短汛限水位的持续时间可以在不影响防洪的情况下增加水库的发电效益,并且对水库最终的淤积平衡影响不大,由此造成的航运损失完全可以用很小的发电效益通过工程措施来补偿。4、运用重庆河段二维水沙数学模型计算分析了三峡水库蓄水后及坝前水位优化情况下重庆河段的冲淤变化情况,综合考虑了上游水库修建的影响及整治工程投入后对航道的改善效果,对调度方式改变对局部河段的冲淤影响做了进一步研究。结果表明,优化调度的进行仅加快了河段淤积的发展,对河段淤积分布及最终的淤积平衡影响不大。上游水库的修建及整治工程的投入将更加有利于优化调度的进行。更多还原

【Abstract】 Reservoir plays an important role in the national economic development. Building reservoir is an effective means to change the temporal and spatial asymmetry of the distributing of the water resource, building reservoir is also an important part of the system to reduce flood and develop the water resource. The benefit of the reservoir is developed through the reservoir operation, and the operation regulation has a consanguineous relation with the deposition development, distributing and the silt-stable in reservoir.In this paper, based on data analysis and calculating, the character of deposition development and the silt-stable in reservoir is researched, and the influence on deposition development and silt-stable lead by the operation regulation of reservoir is researched farther. The analysis of water and sediment, deposition process, and substaintial mechanism is lay particular stress on. Besides these, the operation regulation of the Three Gorges Reservoir is optimized. The main production is listed.1. Through analyzing the deposition development and the silt-stable of reservoir, a conclusion is that the silt-stable is kept with the erosion in flood period and deposition in low-water period under the regulation of storing clear water and discharging muddy water. After the silt-stable is get, the change of longitudinal profile is decided by the transport capacity of the flood period to discharge the muddy in this period and the deposition in high water level period.2. Based on sediment mathematical model, the deposition development of the Three Gorges Reservoir and the influence of the characteristic water level on the sediment deposition in the reservoir are researched. With certain incoming flow and sand, reasonably changing the duration of flood control water level and reasonably changing the normal water level before flood period or after flood period will increase the deposition in storage period and increase the press to discharge muddy water, if the increased deposition doesn’t exceed the affluent transport capacity, the silt-stable will not change. Whether the duration of flood control water level changes the silt stable is decided by the increased deposition is discharged in the effective erosion period. If the increased deposition can’t be discharged in the effective erosion period, the silt-stable will change. 3. The benefit and the effect on sediment deposition brought by optimizing the operation regulation of the Three Gorges Reservoir is researched, a conclusion is drawn that reasonably reducing the duration of flood control water level can increase the electric power benefit without affecting flood control, besides, this will not change the silt-stable and the navigation loss can be compensated by the benefit with engineering measure.4. The erosion and deposition in Chongqing Reach are calculates and analyzed in different optimizing operation regulations, and the effect of the reservoir built upriver and the regulation works is considered, the influence on the erosion and deposition in local reach brought by the change of operation regulation is researched farther. It indicated that optimizing operation regulations not change the distributing and the silt-stable only quicken the deposition development. the reservoir built upriver and the regulation works put in practice will benefit to put the optimized operation regulation into practice.更多还原