山区大型河流弯曲分汊河段航道整治思路与措施

铜鼓滩为弯曲分汊浅险滩,弯槽为枯水航槽,上口水浅,不满足尺度要求,中段航槽落湾,弯曲半径小,下口流速大,流态乱,上下水船舶航行危险。通过叙泸段工程整治,该滩碍航问题得到解决。基于模型试验成果和工程实际效果,通过研究该滩水沙特点和碍航特性,对治理思路与整治措施进行剖析。该类滩险主流洪水趋直,枯水落湾,洪水面流与底流分离,面流趋直,底流携带泥沙落弯;可开辟窄深型直汊通航,辅以江中整治建筑物束水维持航槽稳定;考虑到水沙分离的规律,应合理确定分流点,使水流归直槽,泥沙仍走弯槽。

Channel regulation idea and measures of curved branch of mountainous river

Togngu rapids is a curved branch shoal-rapids which is characterized by dangerous navigation. The regulation of Xu-Lu section has solved the problem of navigation obstruction of Tonggu rapids. Based on the model test result and according to the engineering effect, we research the water-sediment characteristics of navigation-obstruction features, and probe into the regulation idea and measures for the rapids. The main flow of the rapids tends straight at the flood and falls in the bay in the dry season. In the flood season the upper flow and lower flow are separated and the upper flow tends straight, the lower flow brings mud and turns to the bending area. We can dig narrow deep straight channel assisted with regulation buildings in river to guarantee the channel stability; Considering the separation law of water and sand, we should determine proper diversion point to make water run through the straight channel while sand goes through the bending channel.