库区交汇流河段泥沙淤积特性研究

库区交汇流河段的泥沙淤积是河流再造床过程的突出表现,也是影响水库正常运行的重要因素之一.为了研究其对水库正常运行的影响,在总结现有交汇区泥沙冲淤变化研究成果的基础上,以辽宁大凌河白石水库为研究对象,分析不同来沙量、交汇角、干支流洪水特征对不同位置的库区交汇流河段泥沙淤积特性的影响.研究表明,位于常年库区的交汇流河段,在来沙量、交汇角、干支流洪水遭遇几率相同的情况下,其淤积幅度远大于位于变动回水区的交汇流河段;白石水库常年库区的牤牛河交汇区淤积强度较大,交汇区干流纵向上形成凸起的沙坎;沙坎的淤积发展将会给水库的正常运用带来不利影响.

Study on Sediment Deposition Characteristics at River Confluence in Reservoir Area

Sediment deposition at confluence reaches in reservoir areas is a characteristic morphological process, as well as one of the important factors that affect normal operation of reservoir. In order to investigate its impact on normal operation of reservoir, this paper based on the summaries of existing studies on change of deposition and erosion at confluence reaches. Furthermore, used BaiShi Reservoir on Daling River in Liaoning as the research object, explored the influence of different coming sediment, confluence angles and flood feathers at main stream and branches on sedimentation characteristics at different confluence reaches in reservoir areas. Research results show that under the same condition of coming sediment, confluence angle and probability of flood at main stream and branches, sediment deposition in confluence reaches of perennial reservoirs is much bigger than that of fluctuating backwater area; sediment deposition in confluence reaches of Mangniu River is relatively bigger in perennial reservoirs of BaiShi River, sand bars are formed at longitudinal direction in main stream of confluence reaches; sand bars development will bring adverse effect to reservoir normal use.