滩势转移法在澜沧江急浅滩整治中的应用

Application of beach potential transfer method in regulation of Lancang River rapid shoal

急浅滩是山区河流常见的滩险类型,常规整治方法难以奏效,为此提出滩势转移的整治方法。该方法将原急滩滩势转移为新滩,形成缓流区等供船舶上行的滩段,旨在整体达到通航条件。应用河工模型试验研究手段,以澜沧江曼厅大沙坝河段的无名洲急浅滩为例,分析滩险特性和成因,指出扩大泄水断面法等常规整治方法难以整治的根由,阐明滩势转移法的基本思路、工程布置以及整治效果的分析方法,得出滩势转移法的适用条件和范围。滩势转移法适用于滩间关联性较强、常规整治方法影响大的滩群整治中,原滩整治后消滩指数X_(F)不宜过低,以0.8~1.0为宜;新滩需要较强的束水作用,但形成的急滩碍航区不能过宽,需留有上滩适航区。

Rapid shoal is a common type of beach danger in mountainous rivers,and it is difficult to be effectively regulated by conventional regulation methods,so the regulation method of beach potential transfer is put forward.The method is to transfer the original beach to the new beach,which has conditions to form a slow flow area for ships to go up to achieve overall navigation conditions.Taking the Wuming Beach section in Manting reach of Lancang River as an example,this paper analyzes the rapids characteristics,points out the causes of the difficulty by conventional regulation methods such as expanding the drainage section method,expounds the basic idea,engineering layout and analysis method of regulation effect of the beach potential transfer method,and describes the applicable conditions and scope of the beach potential transfer method.The beach potential transfer method is ideal for regulating beach groups with strong interrelatedness and significant impact from conventional regulation methods.The beach reduction index X_(F) should not be excessively low after initial regulation,and 0.8—1.0 is suitable.The new shoal requires effective water confinement,but the resulting hazard area must not be excessively wide,ensuring a navigable area for upstream navigation.